Two people were killed and seven injured in a series of explosions at an arms depot of a military garrison in the Colombian city of Medellin, authorities said according to dpa. The cause of the explosions were still being investigated, a spokesman for the Civil Defence force said. Local media speculated it may have been the result of a grenade accidentally detonated. The military installation was immediately evacuated. Media reports said the two killed were soldiers who happened to be near the depot, while it was unclear if the injured were soldiers of civilians.