BARRON, Wis. -- Investigators searching for Jayme Closs, a Wisconsin girl whose parents were gunned down in their home, are asking for help tracking down two vehicles.
RELATED: Amber Alert: Teen missing, parents found dead in Barron, Wisconsin, home
The sheriff's department received a 911 call from the 13-year-old girl'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.
RELATED: Amber Alert: Missing Wisconsin teen Jayme Closs in danger, not a runaway; parents found dead in Barron County, sheriff says
Barron County Sheriff Chris Fitzgerald said during a news conference Monday that investigators are looking for two vehicles in connection with the case: a red or orange Dodge Challenger and a black Ford Edge or an Acura MDX. He did not release license plate numbers or say how the vehicles might be tied to the case.
Authorities are asking for 2,000 volunteers to resume a ground search for clues on Tuesday morning. A 100-volunteer search on Thursday found nothing, but Fitzgerald says tips led investigators to resume the search.
RELATED: Jayme Closs disappearance: A cryptic 911 call, slain parents, and a missing Wisconsin girl
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.
RELATED: Police: 'Every second counts' in search for missing Wisconsin girl Jayme Closs
Barron is a rural western Wisconsin city about 80 miles northeast of Minneapolis.
Meanwhile, Jayme's classmates planned to hold a vigil for her Monday evening at the Barron High School football stadium.
Jayme Closs disappearance: Police seek 2 vehicles in search for missing Wisconsin girl