CHENGDU, April 27 -- Eight workers are missing after a gas explosion in a coal mine in southwest China's Sichuan Province on Monday afternoon, local authorities said.

The mine in Fulu Town, Leshan City, was undergoing a safety overhaul when the blast occurred at 1:30 p.m., according to the publicity department of Leshan city government.

Three workers were injured and have been sent to hospital. The rescue is ongoing.

The licensed mine had a yearly capacity of 90,000 tonnes, the department said.