A Chinese man who was being repatriated from Vietnam along with 15 other migrants seized a gun from a border guard on Friday, triggering a gunfight and standoff in which five Chinese nationals and two Vietnamese guards died, the Vietnamese government said.

Authorities detained the 16 Chinese - 10 men, four women and two children - after they entered the country in Quang Ninh province, the regional government said in a statement.

As guards checked their papers in a room at the Bac Phong Sinh border crossing, one of the Chinese grabbed an automatic weapon from a guard and began firing, the statement said. A standoff ensued, with some of the men holed up in an office, it said.