(Reuters) - Vietnam has deployed troops to contain a rare protest by ethnic Hmong Christians, some of whom were calling for an independent kingdom, diplomatic and other sources said on Friday, and the government indicated the unrest was still going on.

The demonstration by as many as 7,000 people in the far-flung mountains of Dien Bien Province, near the northwestern border with Laos and China, began several days ago, but details were scant from the hard-to-access region.

Several officials in the area were contacted by telephone but declined to comment.

A Catholic priest based close to the region, citing followers in the area, said troops had been deployed and the protesters had detained at least one government official sent to negotiate.

Demonstrations on this scale are rare in Vietnam, where the ruling Communist Party brooks no opposition.

Dien Bien is one of Vietnam's poorest provinces and people who have travelled there say road, water and power infrastructure in rural areas is rudimentary.

Vietnam has 54 recognised ethnic groups including numerous minorities in its northern and central mountains, some of whom opposed the central government in the years after the end of French colonial rule.

Hmong are hill people, originally form southern China, some of whom have migrated to mountainous parts of Vietnam, Laos, Myanmar and Thailand.

Pham Thanh Binh, a Catholic priest based in the hill town of Sapa, who oversees followers in the area where the protest was taking place, said his contacts in the region told him the military had cordoned off demonstrators and cut electricity and telecommunications.

Troops were not allowing people in or out of the protest area and the demonstrators had detained one or more government officials sent to negotiate. It was unclear when that happened or if the officials had been released.

The U.S.-based Centre for Public Policy Analysis, which advocates for the Hmong, said 28 protesters were killed by the army in a crackdown, but that could not be verified.

A U.S. embassy spokesman said its diplomats had not confirmed reports of violence.

"SUPERNATURAL FORCE"

"We urge all parties involved to avoid violence and resolve any differences peacefully and in accordance with Vietnamese law and internationally recognised human rights standards," the U.S. embassy spokesman said.

Vietnamese Foreign Ministry spokeswoman Nguyen Phuong Nga said in a statement, quoting a government official from the region, "several" Hmong had gathered under the belief that a "supernatural force" would lead them to the promised land and they would have health, happiness and wealth.

"Taking advantage of the situation some bad elements tried to provoke the crowd and mobilise to establish an independent 'kingdom' of the Hmong, disturbing the social order, security and safety of the locality," Nga said in the statement late on Thursday.

Authorities in the region sent officials to "convince" the demonstrators that they should not believe in fabrications and that the push for independence led by bad elements went against Vietnam's policy of national unity, she said.

Some of the Hmong demonstrators had returned home, she said, but "the situation in Muong Nhe is still being resolved by all levels of party and government so that the lives of the compatriots there can return to stability at an early time."

A diplomatic source said 5,000-7,000 people had been involved in the unrest and one of the demonstrators had apparently proclaimed himself king.

The BBC reported in Vietnamese that army units had been sent to quash the demonstration, which started on April 30, a national holiday in Vietnam to celebrate the liberation of the Saigon, as the main city in the south was known, at the end of the Vietnam War in 1975.

The BBC quoted an official in the area as saying authorities had tried to negotiate with the demonstrators.

On May 7, 1954, Communist guerrillas defeated French colonial forces in the fabled battle of Dien Bien Phu, in Dien Bien. Almost exactly 21 years later the Communists went on to depose the U.S.-backed South Vietnam government.

http://uk.reuters.com/article/2011/05/06/uk-vietnam-hmong-protest-idUKTRE7450Q120110506