KARACHI (Agencies) - Three suicide bombers blew up their explosives-laden vehicle when they were challenged by police on the seafront of the provincial capital Wednesday, killing two policemen. The three terrorists, including a woman, were travelling in the explosives-laden vehicle when police flagged down the motorists in the Seaview area at about 10pm. The men were killed when they detonated the explosives in the van, SSP Tariq Dharejo told the media at the blast site. Police tried to stop the vehicle and they blew themselves up. The three people were killed and we have found weapons on the spot. One of the men was wearing a (suicide) vest, Dharejo said. Two policemen, who were chasing the van on a motorcycle, were wounded by the blast. Both of them succumbed to injuries later, police officials said. The blast occurred in an uninhabited area along the seafront located a short distance from a park and a restaurant. The policemen were chasing the Suzuki highroof and exchange of fire took place and after a chase the people in the vehicle detonated themselves, an official said. The bombers may have been planning to target a hotel or a 'mela (fair) to be held in the area, officials said. TV channels reported that intelligence agencies had warned of a possible attack with an explosives-laden vehicle in Karachi. The martyred policemen were identified as Maula Baksh and Muhammad Safeer. The law enforcement agencies cordoned off the area while rescue and emergency response teams reached the site. Police found several suicide vests, grenades, night vision goggles, AK-47s, a wig and a burqa in the wreckage of the van, officials said.