KANDAHAR (Reuters/AFP) - A suicide bomber wearing an explosive vest attacked a patrol of Western and Afghan troops in southern Afghanistan on Saturday, killing at least two civilians and wounding 21, district officials said. Abdul Qayum, governor of Shahjoy district in Zabul province, told Reuters the attacker struck as troops were patrolling a market in the district. Lieutenant-Commander Sam Truelove, press officer for US and NATO-led forces in the capital Kabul, confirmed that there had been a blast but had no further details. International forces were on a foot patrol in Shahjoy town when a suicide bomber on foot detonated himself alongside them. In the incident, 21 civilians were wounded and two of them were killed, said Qayoum. The deputy police chief of Zabul province confirmed the attack, giving a slightly different wounded toll. It was a suicide attack that resulted in 22 (Afghan) people wounded. Two were killed so far, Ghulam Jailani told AFP.