Six soldiers and three supporters of a slain anti-US preacher were killed yesterday in clashes that began six days ago in the mountain region of northern Yemen. Security officials said armed followers of Hussein Badruddin Al-Houthi, who was killed by government forces last year, attacked a military post in the in the Kahlan area of Saada province, 250 km north of Sanaa, killing six soldiers and injuring 13 others. Three of the attackers were killed in a heavy exchange of fire that lasted more than half an hour, said the officials. They said five other dissidents were arrested. Local sources in Saada said insurgents fired a missile at a military vehicle near a checkpoint, setting it a blaze. It was not clear whether the attack left casualties.