BOGOTA, June 4 (Xinhua) -- Colombian rescue teams on Saturday continued to search for eight missing miners in a coal mine where an explosion occurred on Monday, killing at least seven.

Almost 90 percent of the interior of La Mestiza coal mine, located in northern Colombia, had been destroyed and rescue operations have been going on for more than 120 hours, said Jhon Olivares, secretary of sustainable energy mining management of Norte de Santander, a department in northeast Colombia.

"There was a very strong explosion due to the accumulation of methane inside the mine," Olivares told local media. "There are a number of gases such as monoxide that make tasks difficult."

The miners are trapped 300 meters underground, according to rescue authorities.

One miner found at the entrance to the mine was rescued alive but died of serious injury on Tuesday in a medical center in Cucuta, the capital city of Norte de Santander.