A powerful grenade exploded in the office of the Manipur Public Works Department here today.

The grenade, suspected to have been kept on the top floor of the three-storey building where the chief engineer’s office is located, exploded at around 11.30 a.m.

It was not immediately known if any employee was injured or whether the chief engineer was in his office at the time of the explosion, official sources said.

Manipur Director General of Police, Mr Y. Joykumar, has rushed to the spot, which is about 2 km from police headquarters.