BARRON, Wis. -- The search for a missing 13-year-old girl whose parents were killed in the family's northwestern Wisconsin home is expanding Tuesday with as many as 2,000 volunteers expected to comb the area.

The new ground search for Jayme Closs comes several days after an effort with 100 volunteers turned up nothing. Jayme has been missing since Oct. 15 , when deputies responding to a 911 call found someone had broken into the family's home in Barron and shot James and Denise Closs to death.

Authorities believe Jayme, who is not a suspect in her parents' deaths, was abducted.

Barron County Sheriff Chris Fitzgerald said Monday that investigators have received more than 1,300 tips and have closed 1,100 of them. Some of the tips led to the decision to resume the ground search , he said, though he declined to elaborate. A sheriff's deputy and agents from the state Department of Justice and the FBI mapped the area by helicopter Monday afternoon in preparation for Tuesday's search.

"We've determined we'd like to search a bigger search area based on information our investigators have collected," Fitzgerald said. "These tips have led us to this."

Two cars that may have been travelling near the Closs family's home on the night of the killings are being sought in the case, Fitzgerald said.

Investigators are looking for a red or orange Dodge Challenger and a black Ford Edge or black Acura MDX. Fitzgerald didn't have information on the cars' license plates.

Barron, a town of about 3,400 people, is about 80 miles (130 kilometres) northeast of Minneapolis.

A few hundred community members gathered Monday night at the Barron High School football field to support Jayme's extended family and the people looking for her.

First Lutheran Church Pastor Ron Mathews told the crowd that hope has the power to move people beyond despair, fear and anxiety.

"Hope is the sure presence of peace in the midst of grief and deep sadness," Mathews said. Leaders from several churches were on hand to lead small group prayers and comfort a community on edge.