A number of firefighters and officers shave been called to the Civic Centre officers of Wandsworth Borough council.
Emergency services were scrambled just after 10am on Friday morning following a report of an explosion that taken place on Wandsworth High Street.
A full evacuation of Staff and visitors was ordered by council bosses
The explosion is understood to have taken place in the plant room of the council offices.
It is not currently clear if anyone has been injured or the extent of the damage
Wandsworth Council have been approached for comment