Hundreds of civilians were killed as they crossed bridges that a U.S. general and other Army officers ordered blown up at the start of the Korean War, in August 1950, according to ex-GIs, Korean witnesses and U.S. military documents.

An old soldier recalled the critical moment at one bridge.

"I said, 'There are people!' And they said, 'You have to blow it. There's no other way!' " said ex-Army engineer Joseph M. Ipock of Jackson, N.J.

The Associated Press learned of the bridge blowings and two other incidents, machine gun and mortar attacks on refugees, while investigating what happened at No Gun Ri, South Korea, in late July 1950. In that case, as reported last month, veterans corroborated Korean accounts of hundreds of refugees killed on U.S. orders.

One bridge blowing, with its refugee deaths, was recorded briefly in an official Army chronicle, but not until 10 years after the event.

The deaths of civilians, many of them women and children, had been undisclosed as three U.S. Army divisions retreated from advancing North Korean forces across South Korea's Naktong River in July and August 1950.

U.S. commanders also issued standing orders to shoot civilians along the war front to guard against infiltration by North Korean soldiers disguised in the white clothes of Korean peasants, according to declassified Army documents. Military lawyers call those orders illegal.

Just days into his first combat command, the 1st Cavalry Division's Maj. Gen. Hobart R. Gay told reporters he was sure most of the white-clad columns pressing toward American lines were North Korean guerrillas.

"We must find a means to hold these refugees in place," the division commander said.

Days later, on Aug. 3, 1950, Gay waited on the east bank of the Naktong River as his division retreated across the bridge at Waegwan, the last crossing open to North Korean units reported massing more than 15 miles to the west.

His troops had failed in repeated efforts to turn back the flood of refugees, even after firing warning shots over their heads.

"Finally, it was nearly dark," Gay later wrote to an Army historian. "There was nothing else to be done."

Then he gave a fateful command to blow up the bridge, recalled veteran Edward L. Daily of Clarksville, Tenn. As a bridge span collapsed, Daily said, "all those refugees went right down into the river."

"It was a tough decision," Gay wrote to the historian, "because up in the air with the bridge went hundreds of refugees."

The division's 1950 war diary did not report the refugees' deaths. But the later narrative by Gay, who died in 1983, led to a brief mention in an official war history published in 1960.

What happened earlier that August day, however, 25 miles downriver at the village of Tuksong-dong, had not been reported.

Ex-sergeant Carroll F. Kinsman, a veteran of the 14th Combat Engineers Battalion, remembers the streams of white-clad Koreans shuffling across the 650-foot-long Tuksong-dong bridge--women clutching children, old men, overloaded ox carts. The refugees had been searched, but U.S. troops were unable to keep them off the bridge, which had been rigged for demolition.

Soldiers fired over the heads of those crowding across, but the refugees "were abutment to abutment," ex-engineer Leon L. Denis of Huntsville, Ala., recalled in an interview before his death Aug. 31.

When the order came to detonate the explosives wired to the bridge, "it lifted up and turned it sideways and it was full of refugees end to end," said Kinsman, of Gautier, Miss.

"These people were on the bridge, and you saw the spans of steel flying and you knew they were killed," said ex-GI Rudolph Giannelli of Port Saint Lucie, Fla.

In separate interviews, Kinsman, Denis and Giannelli said hundreds of civilians were killed. Ipock said he could see only 30 or 40 refugees from his vantage point.

Kim Bok-jong, 73, a Korean who said he was 200 yards from the bridge, out of view around a hill, remembered that "people rushed back toward us and said many people died when the Americans blew up the bridge."

Kim said others stranded on the shore drowned trying to swim across river.

The veterans said they don't know who gave the detonation order at Tuksong-dong. The operation was noted in the 14th Engineers report with a simple "Results, excellent."

From the bridges, the U.S. Army units moved into defensive positions along the Naktong, in what came to be known as the Pusan Perimeter.

Four 1st Cavalry Division veterans said that on Aug. 2, the day before the bridge blowings, they were among several dozen soldiers retreating toward the Naktong and being trailed by perhaps 80 white-clad Koreans.

In mid-afternoon, five North Korean soldiers--disguised in white--appeared in front of the Americans, they said. Veteran Daily said the North Koreans opened fire and were quickly killed. Another ex-GI, Eugene Hesselman, remembered it differently, saying the intruders surrendered and were led away.

Because it was believed they came from among the refugees, said Hesselman, of Fort Mitchell, Ky., "we got orders to eliminate them [the refugees]. And we mowed them all down. The Army wouldn't take chances."

Scattering too late, every man, woman and child was killed, Daily said. He and veteran Robert G. Russell said they found about 10 disguised North Korean soldiers among the dead. Hesselman said he does not recall that infiltrators were found.

"I didn't like to do it," said Russell, of West Fargo, N.D. "It was just pure survival at the time."

Last year the South Korean government rejected, on a technicality, a compensation claim filed by survivors of the bloodshed at No Gun Ri in July 1950. But after U.S. veterans said their unit killed a large number of refugees under a railroad trestle there, the U.S. Army and Seoul government announced investigations.

Associated Press investigative researcher Randy Herschaft contributed to this report.