Violent Protests Flare Up Again in US Cities: The LatestDemonstrations in dozens of cities around the U.S. over the death of George Floyd, an African American man who died in custody of Minneapolis police, turned violent again Saturday night. Despite curfews and troops from National Guard units in at least a dozen states being called up to help stop violence and looting, the unrest continued late Saturday. Here are the latest updates: 11:20 pm EDT - The Associated Press reports that nearly 1,400 people have been arrested in 17 U.S. cities since Thursday. More than a third of those arrests were made in Los Angeles on Friday, the AP said. 10:45 pm EDT - A police officer in Atlanta was injured after being struck by someone riding an all-terrain-vehicle. The officer "sustained significant injuries," according to the Atlanta Police Department. The rider sustained minor injuries and was arrested, the department said. 10:40 pm EDT - President Trump tweeted support for National Guard troops in Minnesota and police in New York late Saturday. In a tweet criticizing the mayor of Minneapolis, Trump said the Guard troops should have been activated sooner. A few minutes later, the president tweeted that "New York's Finest - a nickname for the New York Police Department - must be allowed to do their job. Protests turned violent For the past four nights, initially peaceful protesting has degenerated into looting, arson and other violence in Minneapolis and neighboring St. Paul, as well as other cities across the United States. “We are under assault,” Minnesota Governor Tim Walz said as he promised “full strength” would be used to restore order. Governors in at least 11 other states -- Georgia, Kentucky, Ohio, Wisconsin, Colorado, Utah, Washington, California, Tennessee, Missouri and Texas -- also activated National Guard troops to help quell protests that in many areas have turned violent. Mayors across the U.S. have instituted nighttime curfews after violence occurred in their cities, including Los Angeles, California; Seattle, Washington; Portland, Oregon; Atlanta, Georgia; Denver, Colorado; Columbia, South Carolina; and Philadelphia, Pennsylvania. The demonstrators are protesting the death of George Floyd, who can be seen in a video lying on the ground with a white officer pressing his knee into his neck. Floyd, who is handcuffed with his hands behind his back on the video, can be heard pleading repeatedly, “I can’t breathe.”