An explosion occurred Wednesday afternoon inside a drug vault at a D.C. police warehouse in Southwest Washington where evidence is stored, according to police and fire officials.

The incident occurred shortly after 2 p.m. in a building near the police training academy in Blue Plains, at the far southwestern tip of the District, near I-295.

One civilian suffered minor injuries and was taken to an area hospital, officials said.

The cause of the explosion on D.C. Village Lane SW was being investigated by the D.C. Fire Department and was undetermined Wednesday afternoon. Dustin Sternbeck, the chief police spokesman, said the blast occurred inside the drug vault.

The extent of damage to the vault and to potential evidence could not immediately be determined.