Barron County Sheriff's remained at the scene of the home where 13-year-old Jayme Closs lived with her parents James, and Denise Wednesday Oct. 17, 2018 in Barron, Wis. Investigators have been searching... (Associated Press) 
 
 Barron County Sheriff's remained at the scene of the home where 13-year-old Jayme Closs lived with her parents James, and Denise Wednesday Oct. 17, 2018 in Barron, Wis. Investigators have been searching for 13-year-old Jayme Closs since deputies responding to a 911 call early Monday found her parents... (Associated Press) 
 
 MADISON, Wis. (AP) — Authorities on Monday called for 2,000 volunteers to help in a ground search for clues in the disappearance of a Wisconsin girl whose parents were gunned down in their home last week. 
 
 After an initial ground search on Thursday in which 100 volunteers helped search for clues into 13-year-old Jayme Closs' disappearance, Barron County Sheriff Chris Fitzgerald said such searches wouldn't resume unless investigators received a tip that justified them continuing. 
 
 Fitzgerald told The Associated Press on Monday that "something triggered" the decision to conduct another ground search that starts Tuesday, but he declined to elaborate. He said he didn't know the exact area of the search but said it would include the land around Jayme's home near Barron, a rural western Wisconsin city about 80 miles (130 kilometers) northeast of Minneapolis. 
 
 The sheriff's department received a 911 call from Jayme's mother early on the morning of Oct. 15. Responding deputies found someone had kicked in the door and that Jayme's parents had been shot to death inside. Jayme, who isn't a suspect in the killings, was missing. 
 
 The sheriff's department, state Department of Justice and FBI have been searching for Jayme since she vanished. Investigators have received more than 1,200 tips and have looked into more than 1,000 of them, according to the sheriff's department. 
 
 The department posted a message on its Facebook page Monday asking for 2,000 volunteers to assist in the next ground search, which was scheduled to begin at 9 a.m. on Tuesday. 
 
 Meanwhile, Jayme's classmates planned to hold a vigil for her Monday evening at the Barron High School football stadium. ||||| One week after 13-year-old Jayme Closs was abducted from her rural Wisconsin home, authorities are looking for two vehicles of interest after cars were spotted near the Closs home around the time of the crime. 
 
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 One car was likely a red or orange 2000 to 2014 Dodge Challenger, based on surveillance videos from homes and businesses, Barron County Sheriff Chris Fitzgerald said at a news conference Monday. 
 
 The second car was likely a 2006 to 2010 black Ford Edge or a 2004 to 2010 black Acura MDX, Fitzgerald said. 
 
 3 vehicles of interest now...pictures just put out by FBI pic.twitter.com/7VdOFUx9C8 — Beth McDonough (@bmcdonoughkstp) October 22, 2018 
 
 Authorities are also asking for 2,000 volunteers to help search for evidence on Tuesday. 
 
 The volunteers must be able to walk on uneven terrain in or around the crime scene, the sheriff's office said. 
 
 This comes after an initial search by 100 volunteers on Thursday. It's not clear if any evidence was found in that search. 
 
 Barron County Sheriffs Dept. via AP 
 
 The mysterious case began in the early hours of Oct. 15 when Jayme's parents, Denise and James Closs, were shot dead in their home, authorities said. 
 
 Police responded to the house after a strange 911 call in which no one spoke. A dispatcher, however, could hear yelling, according to records. 
 
 ABC News 
 
 Jayme was believed to be home at the time of the killings but had been abducted by the time police arrived just minutes after the 911 call, according to authorities. 
 
 "Jayme remains missing and endangered and has been added to the top of the FBI’s Missing Persons list, and is currently on digital billboards nationwide," the sheriff's department said in a statement Sunday. 
 
 .@FBIMilwaukee is seeking information regarding #missing 13-year-old Jayme Closs. If you have info, please contact the Wisconsin Department of Justice Child Abduction Response Team tipline at 1-855-744-3879 or your local @FBI office https://t.co/etpWTWTY9H. pic.twitter.com/WJSJxyNVdX — FBI (@FBI) October 18, 2018 
 
 In the week since she vanished, over 1,300 tips have been submitted so far, and of those 1,100 have been closed, the sheriff's office said. 
 
 Thank you to our friends at the Convenience and Newsbreak Networks for broadcasting the message regarding Missing & Endangered 13 yr old Jayme Closs on screens at gas pumps, convenience stores and truck-stops across the nation. Call 1-855-744-3879 with tips #FindJayme pic.twitter.com/x2mkJbn92n — FBI Milwaukee (@FBIMilwaukee) October 20, 2018 
 
 Community members are set to come together at a "Gathering of Hope" event Monday night to pray for the missing girl. 
 
 Barron County Sheriffs Office 
 
 Barron County Sheriffs Office 
 
 An Amber Alert has been issued for Jayme. Anyone with information is asked to call the 24-hour tip line at 855-744-3879.
– Authorities on Monday called for 2,000 volunteers to help in a ground search for clues in the disappearance of a Wisconsin girl whose parents were gunned down in their home last week. After an initial ground search on Thursday in which 100 volunteers helped search for clues into 13-year-old Jayme Closs' disappearance, Barron County Sheriff Chris Fitzgerald said such searches wouldn't resume unless investigators received a tip that justified them continuing. Fitzgerald told the AP on Monday that "something triggered" the decision to conduct another ground search that starts Tuesday, but he declined to elaborate. He said he didn't know the exact area of the search but said it would include the land around Jayme's home near Barron, a rural western Wisconsin city about 80 miles northeast of Minneapolis. The sheriff's department received a 911 call from Jayme's mother's cellphone just before 1am on Oct. 15; no one spoke, but "a lot of yelling" was heard, ABC News reports. Responding deputies found someone had kicked in the door and that Jayme's parents had been shot to death inside. Jayme, who isn't a suspect in the killings, was missing. The sheriff's department, state Department of Justice, and FBI have been searching for Jayme since she vanished. Investigators have received more than 1,200 tips and have looked into more than 1,000 of them, according to the sheriff's department. The department posted a message on its Facebook page Monday asking for 2,000 volunteers to assist in the next ground search, which was scheduled to begin at 9am on Tuesday. Meanwhile, Jayme's classmates planned to hold a vigil for her Monday evening at the Barron High School football stadium. (The teen was home when her parents were killed.)