A Yemeni army soldier looks on while standing guard at a checkpoint in Sanaa, (AP).
Tribal forces working with the Yemeni army halted on Friday a convoy of militants heading to the southern town of Zinjibar where government troops are fighting to dislodge Islamists, a tribal source said.
One militant was killed and around 10 arrested, the source said, when the tribesmen intercepted the convoy at Moudiya in Abyan province on Yemen's southern coast.
Islamists control many areas in Abyan, prompting fears in the West and neighbouring Saudi Arabia that Al-Qaeda's Yemen wing is exploiting a security vacuum during months of anti-government protests and while President Ali Abdullah Saleh is convalescing in Riyadh after an assassination attempt.
The source said tribes had secured the road from Shabwa province to Shaqra in Abyan, a main highway leading to Zinjibar.
A local official in Zinjibar, the capital of Abyan, said clashes continued there between the army and militants. The army had retaken control of a sports stadium outside the city, he said.
Violence has gripped Yemen since February when protests erupted calling for an end to Saleh's 33-year rule.
Security sources said this week that their forces had killed two Al-Qaeda leaders during an offensive in Abyan as it tries to regain areas seized by the Islamist militants.
But opposition groups and security analysts were sceptical, saying the government wanted to show it has the upper hand in Abyan, which has seen daily bloodshed since militants seized the city of Jaar in March and Zinjibar in May.
Saleh's opponents accuse him of letting his forces ease their grip around areas suspected of hosting militants, in order to convince foreign governments that only he stands in the way of a militant takeover.
Saleh's tenacity has frustrated protesters who thought his time was up when he flew to Saudi Arabia for medical treatment last month following the bomb attack on his palace, leaving impoverished Yemen in political limbo.
As the stalemate goes on, clashes have broken out between the Republican Guard, commanded by Saleh's son, and armed pro-opposition tribesmen who say they are defending the protesters.
Fighting between the Republican Guard and armed men on Thursday killed two people in Arhab, which has been the scene of shelling and gun battles this week. One protester was also shot dead in the city of Taiz, an opposition figure said.
Western powers and Saudi Arabia have tried to contain rising chaos by pressing Saleh to sign a Gulf-brokered plan to hand over power. But he has backed out of the deal three times at the very last minute and has vowed to return to Yemen.