At least three citizens were killed and several others injured in rocket attacks on some villages in Arhab district on the outskirts of Yemen's capital Sana'a where the army has been battling the tribes for months.

Informed sources said the republican guard heavily shelled the villages and that the villages also came under attacks from military camps in nearby districts.

Many have been killed and injured and hundreds of families have been displaced due to the battles that started after the tribes intercepted republican guard units and prevented them from heading to main cities to crack down on antigovernment protesters.

In the past days, the army stepped up the operations in Arhab and Nihm districts after the tribes tired to take over a prominent republican guard camp in Arhab. Jet fighters carried out airstrikes killing and injuring scores including tribes.

Yemen has been plagued by severe crises amid the persistent unrest including acute shortages, battles in some cities including Abyan where the army has been fighting suspected Al-Qaeda militants and a rapidly deteriorating economy.