LOS ANGELES (AP) — More than 5,000 volunteers have fanned out across the city and county of Los Angeles to count the homeless, in what officials say is the nation’s largest homeless census.

The volunteers, equipped with maps, clipboards and flashlights, are scouring 4,000 square miles this week, peering down back alleys, scanning junk-filled cars, and checking crevices around freeway underpasses.

Michael Arnold, executive director of the Los Angeles Homeless Services Authority, says with two-thirds of the county’s 43,000 homeless people living on the street, the only way to count them is to go out and find them.

The federal government requires communities to count their homeless population every two years in order to qualify for homeless assistance funding.

(© Copyright 2011 The Associated Press. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed.)