A Vietnamese border guard opened fire on his colleagues on Saturday, injuring at least two before holing himself up in his border post, in a rare case of gun violence in the communist country.
Civilians are banned from owning guns in Vietnam, a one-party state where a vast police force and army are among the few officials with access to weapons.
On Saturday a border guard in southern Long An province in the Mekong Delta opened fire at his post, hurting at least two people, according to the official Vietnam News Agency (VNA).
The shooter remained armed and locked himself inside the Binh Hiep post -- near the Cambodian border -- as police evacuated the area, according to state media.
"The scene is very chaotic... functional forces are negotiating with the person inside (the station)," local official Nguyen Van Vu was quoted as saying in state-run news site VnExpress.
The shooter was identified as second lieutenant Ta Quang Dat, according to VNA.
Some media reported he had attempted suicide.
A local official told AFP "authorities were working at the scene", without providing further details and requesting anonymity.
Dangerous crimes are extremely uncommon in Vietnam, though in recent years a small number of high-profile incidents have chilled the country.
In 2016 a forest ranger shot and killed two provincial officials in northern Yen Bai province before turning the gun on himself.
And last year, a pipe bomb tore through a police station in southern Ho Chi Minh City, which officials later said was a politically motivated crime carried out by "terrorists".