SANAA (Agencies) - Yemeni warplanes have killed at least 80 anti-regime tribesmen in the northeastern region of Arhab in the space of 48 hours, security officials say. A security official leaked the information to the media on condition of anonymity, a news agency reported on Saturday. The reason for the heavy offensive is believed to have been that the tribesmen had taken over a military camp in the region a few days prior to the attack. While there have yet not been any independent reports to confirm the event, a soldier from Yemens 63rd Brigade who escaped the camp said that the tribesmen had overrun it. Moreover, the soldier added that some 20 troops loyal to Saleh had been killed in the clashes. Scores of tribesmen have lost their lives in military attacks on tribal areas since the beginning of the uprising against the regime of Ali Abdullah Saleh in late January. Moreover, hundreds of pro-democracy protesters have also been killed and thousands more injured by forces loyal to Saleh. Saleh singed a power transfer deal proposed by Persian Gulf littoral states in Saudi Arabia on Wednesday. Under the deal, the Yemeni dictator transfers his presidential powers to his deputy, Vice President Abdrabuh Mansur Hadi, who is expected to form a national unity government and also call for early presidential elections in 90 days. The deal also grants Saleh immunity in return for his resignation. However, protesters have rejected the deal saying they want Saleh prosecuted for the people his forces killed during the crackdown.