An explosion at a coal mine in Indonesia's West Sumatra province killed nine miners, authorities confirmed Friday as rescue workers continued to search for a missing miner after rescuing two others.

The blast, caused by noxious gases including methane, occurred in a mine in Sawahlunto district owned by a private company while the 12 miners were entering the pit.

Rescuers were using blowers and exhaust fans to remove air from the mine to make it safe to enter the area.

"The team struggled to find victims considering the location was quite difficult to (access)," said Octavianto, a spokesperson from the local search and rescue agency who like many Indonesians only goes by one name.

Videos distributed by the National Search and Rescue Agency showed rescuers carrying victims out on stretchers and giving them oxygen from tanks. Other footage showed yellow body bags being carried out from the pit.

Landslides, flooding and tunnel collapses are just some of the hazards miners face.

In April, an overloaded truck carrying 29 people hit a hillside and overturned near an illegal gold mine in Indonesia’s West Papua province, killing 18 people and leaving others injured.

Another major mining-related accident in Indonesia occurred in February 2019 when a makeshift wooden structure in an illegal gold mine in North Sulawesi province collapsed due to shifting soil and the large number of mining holes. More than 40 people died, buried in the mine pit.

Sawahlunto was built by Dutch colonizers as a coal town in the 19th century.

The blast comes a day after a 5.8 magnitude earthquake hit Indonesia's main island of Java on Thursday, reigniting fears just a month after the deadliest earthquake in recent years that killed more than 300 people.