A drug addict and HIV patient shot a man dead on Sunday, following an argument in a gambling den in Hai Phong.
Do Van Be, 39, a guard at the den, shot Do Anh Tuan, 30, with a gun he'd been carrying, killing Tuan on the spot, Tien Phong reported.
Tuan's friends chased after Be, who fired back at them.
Surrendered at his home, following a five hour standoff with the police. Be was taken into custody along with the gun, containing five bullets.
Police say they are collecting evidence to file manslaughter charges against Be.
Be has served two previous convictions on property robbery.