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 (CNN) -- Before the Brooklyn Nets and Cleveland Cavaliers faced off on the basketball court Monday night, several players were already scoring points with protesters outside the arena. 
 
 As they warmed up for the game, Cleveland Cavaliers LeBron James and Kyrie Irving were among the players wearing T-shirts that said "I can't breathe" -- Eric Garner's last words, which have become a rallying cry for protesters after last week's grand jury decision not to indict an officer in his death. 
 
 Outside the Barclays Center, a large crowd of demonstrators swarmed the streets, chanting "hands up, don't shoot" and "black lives matter." 
 
 The crowd erupted in cheers after an organizer told them about the players' T-shirts. 
 
 The NBA players' show of support for protesters comes a week after five players from the St. Louis Rams walked onto the field and raised their palms in the air, demonstrating the "hands up, don't shoot" gesture that protesters have been using in demonstrations over the police shooting of Michael Brown in Ferguson, Missouri. 
 
 Activists have been threatening to disrupt the visit of the Duke and Duchess of Cambridge, who are visiting New York and attending the Nets-Cavaliers game. 
 
 "They need to know this is what America is. ... America is a system where those who benefit from others neglect to see the underclass, the people who are underprivileged, and that's why we're out here," said Jibri Nuriddin, a protester from New York. 
 
 Demonstrations, he said, aren't going to stop. 
 
 "We're going to keep chanting and keep marching," he told CNN from outside the arena. "Everyone's going to know that this is an issue. We're not going to let this issue die." 
 
 Amanda Jack, a public defender in New York, said she joined protests after seeing many of her clients suffer at the hands of what she called a racist system. 
 
 "There can't be any more business as usual when this kind of injustice continues. I think this (basketball game) is one of the examples of consumerism and excess, so it's time. Shut it down," she said. "We've got to address our broken justice system." 
 
 Brooklyn Borough President Eric Adams, a former New York police officer, said protesters have a right to take a stand. 
 
 "There's nothing more American than having the right to voice your concern," he told CNN's "The Situation Room." "We want them to be constructive and not destructive." 
 
 The New York demonstration was one of a number of protests across the United States Monday night, days after a grand jury in New York City decided not to indict a police officer in Eric Garner's death and two weeks after a Missouri grand jury decided not to indict former Officer Darren Wilson in Brown's killing. 
 
 In Washington, demonstrators protesting police violence laid down in the street several blocks from the White House on Monday, blocking rush hour traffic. 
 
 Protesters chanted, "black lives matter" and "off the sidewalks, into the streets." 
 
 One woman held a sign that said, "Stop killing us." 
 
 The demonstration blocked traffic at cross streets along Connecticut Avenue, a major thoroughfare that connects the White House to upper northwest Washington. 
 
 Collette Flanagan of Dallas told protesters her unarmed son was killed by police. 
 
 "Our babies should be here in the prime of their lives," she said. 
 
 And Berkeley, California, protestors temporarily shut down the I-80 freeway in both directions Monday night. 
 
 New York mayor praises police 
 
 New York Mayor Bill de Blasio praised police officers' handling of the protests. 
 
 "They've respected people's right under the First Amendment to express their views. They've kept the peace. They've kept order," he told reporters Monday. "We had only a handful arrests the last two days, which is extraordinarily impressive given all of the activity that's happening." 
 
 De Blasio says he understands parents who are worried about what might happen if their kids encounter police. The New York mayor says he's had to warn his own son about that possibility. 
 
 "When he was just becoming a teenager, you know, the conversation was a difficult one and a complicated one, because you're trying to say to a young person who obviously looks up to police, you know, be careful and be smart and respect the police, but also recognize that there are these realities to be grappled with -- and that's a tough conversation to have with a young man," he said. 
 
 De Blasio is white. His son is biracial. 
 
 "This is a national reality. It's not just a New York reality," de Blasio said. "And that, unfortunately, is further evidence of how much more we all have to learn from each other. ... The goal is to get to a day when no parent feels they have to have that conversation." 
 
 Protesters flood California streets 
 
 A day after a heated standoff on a freeway between protesters in Oakland, California, and the California Highway Patrol, demonstrators in the area took to the streets again Monday. 
 
 CNN affiliate KTVU showed throngs of protesters in the streets in Berkeley, California. 
 
 It was a peaceful scene, KTVU reported. But violence erupted in earlier Berkeley protests Monday. 
 
 Some protesters looted and vandalized businesses, police spokeswoman Jennifer Coats said. 
 
 One protester was struck in the head with a hammer when he tried to keep fellow protesters from damaging and looting a Radio Shack, she said. The man was hospitalized, but his injuries are not believed to be life-threatening. 
 
 Two Berkeley officers also suffered minor injuries. Coats said five people were arrested, but she did not know the charges. 
 
 On Sunday night, demonstrators flooded a highway in Oakland, California. Some threw explosives, bottles and rocks at officers, authorities said. Officers responded by deploying gas and arresting eight protesters. In the end, two officers suffered minor injuries. 
 
 Police said five patrol cars were damaged. 
 
 Not everyone is on their side 
 
 In Imperial, Missouri, demonstrators staged a different kind of protest Sunday. 
 
 They burned St. Louis Rams football jerseys after the protest by players last week, CNN affiliate KSDK reported. 
 
 "Why would you do something like that? It's utterly ridiculous," said Larry Magee. "I think the Rams ought to pack their bags, and I'll give them a plane ticket back to L.A." 
 
 Daughter: 'This is not a black-and-white issue' 
 
 Garner's daughter Erica said she was deeply moved by the diversity of protesters who have demonstrated across the country. 
 
 "This is not a black-and-white issue. This is a national crisis," Erica Garner said. 
 
 U.S. Attorney General Eric Holder has announced a federal civil rights investigation into Garner's death. 
 
 And on Monday, New York Attorney General Eric Schneiderman said he was asking the state's governor to issue an executive order to change the way the state reviews cases such as Garner's. 
 
 The order, Schneiderman's office said in a statement, should direct the attorney general "to investigate and, if necessary, prosecute cases involving unarmed civilians killed by police officers." 
 
 "The horrible events surrounding the death of Eric Garner have revealed a deep crisis of confidence in some of the fundamental elements of our criminal justice system," Schneiderman said. 
 
 Unlike with the Michael Brown case, a video showing the moments leading up to Garner's death has been widely circulated. 
 
 Erica Garner says that video has struck a nerve with many. 
 
 "For white people to come out and show how deeply they was hurt and like Asians and, you know, different people from different nations and different parts of the world to come out and show that they felt the same way I felt on that video, I greatly appreciated it. It's like a sense of I'm not the only one that feels this way." 
 
 This story was based on reporting by Julian Cummings, Athena Jones, Joe Sutton, Holly Yan, Dan Simon, Stephanie Gallman, Wayne Sterling, Laura Ly, Daniel Verello and Deborah Feyerick and was written by Catherine E. Shoichet, Holly Yan and Ralph Ellis. ||||| December 8, 2014 10:46 PM 
 
 LeBron James #23 of the Cleveland Cavaliers wears an ‘I Can’t Breathe’ shirt during warmups before his game against the Brooklyn Nets during their game at the Barclays Center on December 8, 2014 in New York City. (Photo by Al Bello/Getty Images) 
 
 NEW YORK (CBSNewYork/AP) — LeBron James wore an “I Can’t Breathe” shirt before the Cavaliers took on the Nets on Monday night, much like Derrick Rose did this weekend. 
 
 Rose warmed up in the shirt Saturday before Chicago played Golden State. It refers to Eric Garner, who died July 17 after a New York City police officer placed him in a chokehold when he was being arrested for selling loose, untaxed cigarettes. 
 
 A recording of the arrest showed Garner gasping, “I can’t breathe” during the fatal encounter, and thousands have protested a grand jury decision not to indict the officer since the announcement on Wednesday. 
 
 “It was spectacular,” James said of the shirt. “I loved it. I’m looking for one.” 
 
 James found a shirt, and was seen wearing it during warmups. Several other players from both teams wore similar shirts, including Kevin Garnett and Deron Williams of the Nets. 
 
 Britain’s Prince William and Princess Kate attended the game, where they met and posed for photos with James. 
 
 “It’s a huge honor,” James said at the Cavaliers’ practice. “The stuff you read about, people like them only in books growing up, and to hear that they’re coming in town to see me play and they want to see me do what I do best, it’s a huge honor.” 
 
 James said he was excited to get to meet the royal couple. 
 
 “I’ve had people from all across the board as far as stature, but the President of the United States, that was pretty huge,” he said. “To have those two, to say they were traveling here and one of the things that they wanted to do was see me play, it’s a pretty big deal in my household.” 
 
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 (TM and © Copyright 2014 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2014 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.) ||||| LeBron James talks about himself and Kyrie Irving wearing "I can't breathe" T-shirts during warm-ups before the Cavaliers' game against the Nets. (1:53) 
 
 BROOKLYN -- Several players on both the Cleveland Cavaliers and Brooklyn Nets, including LeBron James, Kevin Garnett, Kyrie Irving and Deron Williams, wore black "I Can't Breathe" T-shirts during pregame warm-ups Monday, following in the footsteps of Chicago Bulls guard Derrick Rose who wore the same shirt in a game Saturday to show support for the family of Eric Garner. 
 
 Of his T-shirt, LeBron James said: "It's not a Cavs thing. It's a worldly thing." Al Bello/Getty Images 
 
 "It's not a Cavs thing," James said before the game. "It's a worldly thing." 
 
 On several occasions in the past couple weeks, James has spoken out about the deaths of Mike Brown in Ferguson, Missouri, and Tamir Rice in Cleveland. Like Garner, Brown and Rice were both African-American males that died because of a confrontation with a police officer. 
 
 "It's just for us to make a [statement] to understand what we're going through as a society," James said when asked about the T-shirt. "I've been quoted over and over about what's going on as far as it's more of a notion to the family, more than anything. Obviously, as a society we have to do better. We have to be better for one another. It doesn't matter what race you are. It's more of a shout out to the family more than anything, because they're the ones that should be getting all the energy and effort." 
 
 James told reporters on Sunday he was "looking for" a T-shirt like the one Rose wore. Nets guard Jarrett Jack heard James' comments and supplied the shirts for players on both teams to wear. 
 
 "The power of social media," James said. 
 
 Editor's Picks Whitlock: Why black folks can't breathe Sensitivity training for police won't change the laws that have suffocated black society since Jim Crow laws were repealed, Jason Whitlock writes. 
 
 Before the game, Jack, who played for Cleveland last season, told reporters he offered the T-shirts to members of the Cavs. 
 
 "I just heard people's opinion on the topic, and I know [the Cavaliers] are on the road, this is the place where it happened, so if they wanted to be a part of the cause or make a statement without actually necessarily saying any words, I definitely extended the invitation," Jack said. 
 
 "Obviously Kyrie was my teammate, so I reached out to him, I heard 'Bron say something about it when Derrick Rose took the stance on it, so I reached out to my people out here, Excel Sports Management [Jack's agency], they was able to make it happen, they made a few shirts for those guys happen over there, so I know us as a team we're gonna go out and try to make a stance and show that we're a team that's not with prejudice. We want to have tolerance for everybody. And I just want to allow those guys to come be a part of it as well as much as we could."
– As Eric Garner protesters staged a "die-in" outside Barclays Center in Brooklyn last night, players from both the Nets and the Cleveland Cavaliers donned T-shirts to show their support. LeBron James was among those wearing an "I Can't Breathe" shirt during a pregame warm-up, referring to Garner's last words, CBS reports. The Chicago Bulls' Derrick Rose wore one on Saturday, and after James told reporters he was looking for the same shirt, the Nets' Jarrett Jack supplied them to both teams. James tells ESPN that the shirt is mostly a "shout out to the family," but "as a society we have to do better. We have to be better for one another. It doesn't matter what race you are." James also met Prince William and his wife, Kate, who were at the game and posed with him for photos. "The stuff you read about, people like them only in books growing up, and to hear that they're coming in town to see me play and they want to see me do what I do best, it's a huge honor," the player tells CBS. Outside the arena, the crowd of protesters cheered when they were told about the shirts being worn by James and other players, including the Cavaliers' Kyrie Irving and the Nets' Kevin Garnett and Deron Williams, CNN reports.