ADEN (Reuters) - Armed militants killed four Yemeni soldiers in an attack on a checkpoint in the south of the Arab country on Saturday, a local official said, a day after 12 soldiers were killed in a suspected Al-Qaeda ambush. Six of the assailants were wounded in the clash which took place in the southern province of Lahj, the official told Reuters. Eight soldiers were injured on Saturday when their vehicle came under fire in the southern city of Lawdar, the site of Fridays suspected Al-Qaeda ambush which killed 12 soldiers, another local official said. Yemen is trying to quell a resurgent wing of Al-Qaeda that has stepped up attacks on Western and regional targets in the poor Arabian Peninsula state, a neighbour of oil giant Saudi Arabia. Yemen also faces growing separatist militancy in the south while it tries to maintain a shaky truce with rebels in the north. The country is a focus of Western security concerns after two US-bound parcel bombs were intercepted in Britain and Dubai in October, a plot claimed by Al-Qaedas Yemen-based regional wing.