Thirteen members of Cuba’s rebel armed forces (FAR) are missing after an explosion at a warehouse of weapons and ammunition yesterday (Tuesday) in the eastern part of the country, authorities said.

The explosion occurred in Melones, 730 kilometers east of Havana, and led to the emergency evacuation of more than 1,200 residents from the area, the Armed Forces Ministry said in a statement broadcast on public television.

Nine soldiers, two non-commissioned officers, and two officers were declared “missing,” according to the statement. The blast occurred in a building where “old ammunition was stored.”

The cause of the explosion was not specified. According to Cuban media, it was probably due to a fire.