About 300 Marine base workers walked shoulder to shoulder through a southern Arizona neighborhood Thursday in search of any stray ammunition from the crash of a bomb-laden Harrier jet (search).

As each section was cleared, officials planned to let residents return to the last 52 homes still evacuated after Wednesday's crash in Yuma, said James Stover, the city's public affairs manager.

Hundreds more evacuees had been allowed to go home late Wednesdhours after the jet plunged into a backyard while trying to land at Marine Corps Air Station-Yuma (search), about 185 miles southwest of Phoenix.

The pilot ejected safely before the crash, and one civilian on the ground had a minor cut. Two homes had structural damage, Marine Cpl. Michael Nease said.

The plane's four 500-pound bombs were safely removed. They have devices to prevent detonation if they are accidentally dropped from the aircraft or hit the ground in a crash, Nease said. The plane was also carrying 300 rounds of 25-milimeter ammunition, none of which exploded.

Stover said most of the ammunition had been accounted for. "This is again to make sure there are no loose ends," he said.ay,

The plane crashed and burst into flames about a mile from the base. Marine investigators were trying to determine what caused the crash, Nease said.

The AV-8B Harrier (search), a light attack aircraft that can take off and land like a helicopter, was the fourth such jet from the Yuma air station to crash in 18 months. A Harrier crashed in Yuma on Dec. 2 and two crashed in December 2003. In each case, the pilot ejected safely.