An explosion in the lobby of the Marriott hotel in downtown Islamabad, Pakistan has left several people injured.

A State Department official in Washington said 11 U.S. embassy staffers were having an evening meal there, and one of them was among the injured.

Initial reports said the explosion was caused by an electric short circuit. But Pakistani Television quoted police as saying it was an explosion, not a short circuit.

However, Interior Minister Aftab Ahmed Khan Sherpao said there was no evidence of any terrorist activity or any bomb blast.

Witnesses said the glass entrance of the heavily guarded hotel was shattered, although the damage to the structure of the hotel was not severe.

They said the explosion appeared to have occurred at the lobby entrance, where a security guard is posted.

Some information for this story provided by AFP.