COLOMBO, April 25 (Xinhua) -- An explosion occurred inside Sri Lanka's army headquarters in Colombo Tuesday, causing serious injuries, police said.

    It was not immediately known the cause of the explosion and the investigation is being undertaken, said an officer from Sri Lanka's police headquarters.

    A local radio said at least 11 people were injured in the explosion which happened early afternoon.

    High-ranking Sri Lankan military officials work in the tightly guarded headquarters. Enditem