Two American photographers and two Red Cross workers were released yesterday after being held for three days by Vietnamese soldiers who captured them at a refugee camp on the Thai-Cambodian border, special correspondent John Burgess reported.

The two Americans, Richard Franken, 35, and Georg Lienemann, 31, and Robert Ashe, 27, and Dr. Pierre Perrin, 36, of the Geneva-based International Committee of the Red Corss, reentered Thailand at a bridge near Aranyaprathet after being marched 12 miles to a vietnamese base camp and questioned about foreign relief operations. It was the first time Vietnamese forces had taken Westerners into custody at the border.

Ashe and Perrin told a Bangkok news conference that they were well treated by the Vietnamese, but had been blindfoled twice while passing military installations. Franken and Lienemann, the co-owners of a Bangkok photo agency, have not yet returned to Bangkok from the border area.

The four men were detained Thursday while searching for wounded Cambodian refugees inside the deserted Nong Chan refugee camp, the site of border clashes this week between Thai and Vietnamese troops.

The camp had also been a springboard for the "land bridge" relief operation into Cambodia, which distributed seed and rice to thousands of Cambodian refugees.

Ashe, who has been in charge of relief operations at Nong Chan, told the news conference that the Vietnamese had given him no indication of whether they would allow the land bridge to reopen.

Ashe also told the press conference that they had seen no evidence that the Vietnamese had forcibly taken large numbers of refugees back to Cambodia from the camps they overran, as some refugees have claimed.

Meanwhile, Secretary of State Edmund Muskie, who pledged support to the Thais at the meeting of foreign ministers of the Association of Southwest Asian Nations (ASEAN) in Kuala Lumpur, Malaysia, returned to the United States last night.