Villagers' relatives, testifying before a panel of the US Congress, charged that Vietnamese authorities forcibly prevented Con Dau parish, near the central city of Danang, from burying a woman at the local cemetery in May.

Authorities, who want to move the parish and build a resort, seized the body to cremate and severely beat the villagers, including women and the elderly, the residents said.

Tai Nguyen, who lives in Houston, said tearfully that police came back in July and took away his brother Nam Nguyen, a procession leader, who died two days later in custody after bruises around his body.

Witnesses also testified that a pregnant woman, Le Thi Van, was beaten until she suffered a miscarriage, while at least half a dozen other villagers remain jailed.

Five lawmakers -- including Representative Anh "Joseph" Cao, the only Vietnamese-American member of Congress -- called for a probe in a proposed congressional resolution.

The United States should press the United Nations to appoint an envoy "to investigate ongoing and serious human rights violations in that country, including those violations targeting the villagers of Con Dau," it said.

Vietnam's foreign ministry in May denied any injuries in what it terms a land dispute, describing accounts of mistreatment as an attempt to "smear Vietnam".

But Quang Nguyen, who said that his brother was beaten into signing a confession, explained that the cemetery was more than 100 years old and where "all our brothers and sisters are after they die."

"This cemetery is not a normal piece of land. It is the heritage of our parish," he said.

"We would like to ask your help to save the people of Con Dau so that they can live peacefully on the land of their ancestors and practice their religious rites," he said.

Nguyen said his brother fled to Thailand, where he is hoping to obtain UN refugee status along with around 30 other Con Dau residents.

Thang Nguyen, who represents the asylum seekers as part of the group Boat People SOS, voiced worries over uncertainties in Thailand, which controversially deported some 4,500 Hmong back to neighboring Laos last year.

Despite human rights concerns and war memories, the United States and Vietnam have been steadily expanding cooperation -- which many analysts see as a response to growing concerns about regional heavyweight China.

Vietnam and the United States on Tuesday held their first high-level defense dialogue.

As the nations marked 15 years of normalized ties in July, Kurt Campbell, the top US diplomat for Asia, said: "As I look at all the friends in Southeast Asia, I think we have the greatest prospects in the future with Vietnam."

Representative Christopher Smith, a Republican from New Jersey and lead sponsor of the resolution on the village, attacked Campbell's statement, saying he overlooked Vietnam's "absolutely appalling" human rights record.

"Why would anyone in Hanoi be worried about the United States taking Vietnam to task on human rights with that kind of flowery flattery?" Smith said.