Four workers were killed in a coal mine blast in the northern province of Quang Ninh on Monday.
The explosion happened at around 6 a.m. at the coal mine belonging to a local coal company in Cam Pha City.
Le Kim Long, 27, Nguyen The Anh, 23, Tran Van Tinh and Hoang Van Trong, both 25, were checking electricity system in the coal pit when the blast took place.
More than two hours later, rescuers managed to take the dead body of one of four workers out.
The remaining three were dead but rescuers could not bring them out because of high temperatures inside the pit.
Initial investigations speculate the explosion may have been caused by a mistake in work process, a Vietnamnet report said.