Moscow, Aug 25 (RIA Novosti) Four police officers were killed Tuesday when a suicide bomber blew himself up while they waited for their vehicle at a car wash in Russian North Caucasus republic of Chechnya, police said.

The 'suicide bomber ... activated a home-made explosive device hidden under his clothes. Four police officers were killed on the spot', a police source said.

The incident took place in Shali district. A fifth policeman has been hospitalised with severe wounds.