The death toll of Tuesday's gas explosion in an Indonesian coal mine has increased, with a total of 31 bodies having been recovered.

A small number of miners are still trapped, but it is almost certain they have died because of the high level of carbon monoxide in the mine.

Flames from the explosion shot dozens of metres into the air and a large crater was formed. The mine is located in Sawahlunto, West Sumatra, and is owned by local people. After Australia, Indonesia is the world's top coal exporter.

photo Sawahlunto: Flickr/Bigfloppy