Updated

U.S. Marines searching a Baghdad school made a chilling discovery: scores of black leather vests stuffed with explosives and ball bearings, along with empty hangers hinting that suicide attackers already might be outfitted to explode somewhere in this chaotic city.

More than 40 of the vests -- on hangers and shrouded in plastic -- lay on the floor of a classroom Saturday morning, two days after Marines discovered them in an elementary school in a middle-class neighborhood. Dozens of hangers were strewn on the ground outside the building.

"Odds are high that someone is out there wearing one," said Marine Lt. David Wright, 27, of Goldsboro, N.C. "They were indeed dedicated to do something if they strapped on those vests."

Just 150 yards away, a junior high school held hundreds of huge crates of weapons, rocket-propelled grenades, surface-to-air missiles and shoulder-launched rockets.

Residents of the neighborhood said members of the paramilitary Fedayeen came in about a month ago in pickup trucks in the middle of the night. The Fedayeen fighters unloaded the weapons in the two school compounds, yards from the nearest houses.

The residents said they had no idea what was being unloaded.

"We could not say, `Don't put it here, don't put it there.' We couldn't prevent it," said Zina Selman, 45, whose house is less than 50 yards from the school with the apparent suicide vests.

The Marines discovered the weapons caches Thursday night. A reporter from The Associated Press was given a tour of them Saturday morning, as Marines continued to secure the compound to prevent residents of the middle-class neighborhood from entering.

U.S. troops in Iraq have been on high alert against suicide attacks.

Early in the war, a bomber posing as a taxi driver pulled up to a roadblock north of Najaf, waved to American troops for help, then blew up his vehicle up as they approached, killing four. On Thursday, four Marines and a medical corpsman were wounded when a vehicle blew up as it approached a checkpoint in Baghdad.

In another sign of the threat of suicide attacks, U.S. forces Saturday stopped a bus near the Syrian border that was carrying 59 men of military age who had with them $630,000 in $100 bills and a letter offering a reward for killing American soldiers.

Brig. Gen. Vincent Brooks said the men were trying to leave Iraq. He said he did not know the men's nationalities, nor who had written the letter offering rewards.

The vests were found in what appeared to be a biology classroom with diagrams of cells on the walls. They looked almost professionally made, each nearly a replica of the others.

Each weighed nearly 20 pounds, the black leather filled with blocks of C-4 explosive laced with ball bearings. Wires protruded from the vests.

U.S. Central Command in Qatar said in a statement that Marines found 310 vests -- 160 containing ball bearings and explosives and the rest only explosives. Sixty vests were leather and designed to be worn over clothing, said the statement, which gave no other details.

In a courtyard outside the classroom sat cardboard boxes of black detonators with two red buttons on the end and Velcro on the side, apparently so the detonator could be attached to a vest. Three boxes of dynamite and a crate marked "explosives" were nearby.

Next to the classroom lay stacks of long plastic bags filled with reddish-brown puttylike blocks that appeared to be explosives. Some of it was sculpted onto the back of a metal bar that Marines speculated was a crude effort to make a shaped charge.

Residents said the Fedayeen left the neighborhood about a week ago and lit a fire in that school. When the neighbors ran in to put the fire out they discovered the vests.

"We have children, we have families, what are we supposed to do?" asked Farouk al Amary, 54, whose house is just across the street from the school. "We don't want bombs."

Selman said she left her house when the vests were discovered. But the men of the neighborhood poured sand on the vests to try to dampen potential explosions and she moved back the next day.

At the junior high school, Marines slept in a courtyard just feet from hundreds of crates of ammunition. Several crates of weapons were marked "GHQ Jordan Armed Forces, director of planning and organization, Amman, Jordan."

For the past day, residents had brought the Marines dozens of rocket-propelled grenades, shoulder-launched rockets and even mortar systems found throughout the neighborhood.

The neighbors said the Fedayeen had put the ammunition in their yards, on their roofs and in their parks.

Wright said it appeared an effort to position weapons throughout the neighborhood in preparation for house-to-house fighting that never happened.

Selman said she was sure here neighborhood was not unique.

"All over Baghdad," she said, "there are bombs near people."