An explosion by methane gas ripped through a coal mine in northern Colombia, killing three people, injuring three and leaving at least four more trapped.

An explosion apparently caused by methane gas ripped through a coal mine in northern Colombia, killing three people, injuring three and leaving at least four more trapped, authorities said Wednesday.

Three other miners were rescued with burns to their faces after the explosion at the mine, called El Diamante, in the town of Socha in Boyaca department, authorities said.

So far this year, mining accidents have claimed more than 30 lives in Colombia, most of them in cave-ins.

President Juan Manuel Santos is trying to make expanding mining a pillar of Colombia's economic growth.