Tens of thousands of Yemenis have joined a rally in the capital, Sanaa, to protest the government's handling of an Islamist insurgency in the southern province of Abyan.

The protesters marched to the residence of Yemeni Vice President Abed Rabbo Mansour Hadi on Monday and handed a petition to guards at the entrance. Hadi has been Yemen's acting leader since President Ali Abdullah Saleh was seriously wounded in a June 3 bombing in Sanaa and forced to seek treatment in Saudi Arabia.

The demonstrators accuse the Yemeni government of not doing enough to combat Islamist militants who took control of parts of Abyan in late May. Yemeni opposition activists say Mr. Saleh and his allies have been exploiting the Islamist insurgency to try to show that only he is capable of protecting Yemen from al-Qaida.

The Yemeni opposition has staged five months of near-daily nationwide protests demanding an end to Mr. Saleh's 33-year autocratic rule. Activists also held an anti-Saleh rally on Monday in the southwestern city of Taiz.

In another development, the Yemeni state news agency Saba says gunmen ambushed a Republican Guard patrol Sunday in Taiz province, killing four soldiers and wounding 12 others.