Sofia, August 8 (BTA) - An explosion occurred at an ammunition disposal factory in the town of Kostenets at 8.40 on Friday, the Defence Ministry said. The blast injured four workers, who were taken to hospital. None was injured seriously, according to media reports.

Defence Minister Velizar Shalamanov and Sofia Regional Governor Emil Ivanov are on their way to the scene to coordinate rescue efforts, the government information service said.