Two workers were buried Saturday morning when a rock mine collapsed in the northern province of Hoa Binh, according to a Sunday Vnexpress report.

Eyewitnesses said Dinh Van Tin, 32, and Bui Van Tho, 30, were working at a palate-shaped mine under a mountain when tons of rocks fell and buried them. Their bodies have been found.

The rock mine is being developed by the local Xuan Hoa Company. Residents living nearby said accidents were not unusual at the site.

Police are investigating the case further.