A suicide car bomber hit a NATO convoy in the southern Afghan city of Kandahar on Tuesday (August 22) wounding four NATO soldiers and a passer-by, a spokesman for the force said. The attack happened in the heart of the city close to a NATO base. A vehicle in the convoy was set on fire and secondary explosions coming from it were probably caused by ammunition going off, a NATO spokesman said. Initial reports said four soldiers and a local civilian were wounded, according to NATO spokesman Major Scott Lundy. He did not know the nationality of the wounded soldiers. "I heard a huge bang just outside our office (De-mining office) I saw the foreigners convoy on fire and smoke raising, I don't know about casualties." Said eyewitness Akhter Mohammad and employee of Afghan De-mining office. The bomber was killed in the blast, an Afghan official said. NATO troops quickly cordoned off the site. Canadians make up the bulk of NATO troops in the province, where the alliance took over security responsibility from a U.S.-led coalition force last month. Afghanistan is going through the bloodiest phase of violence since U.S.-led troops overthrew the Taliban government in 2001. Two Canadian soldiers were wounded in an ambush on Monday (August 21) night to the southwest of Kandahar city, NATO officials said. About 2,000 people, most of them militants but including more than 90 foreign troops and scores of Afghan soldiers, police and civilians, have been killed in violence this year.