Naval patrol managed to rescue 30 other migrants off southern coast.
At least four suspected al Qaeda militants were killed in air strikes.
Attackers mounted multi-weapon assault to free inmates.
Shiite and Sunni rivals agreed to truce in wake of deadly clashes.
At least 210 people have been killed in two months of fighting between Shi'ite Muslim Houthis and ultra-conservative Sunni Salafis in northern Yemen, a Salafi spokesman said on Monday.
Two men were military experts working for Defense Ministry.
Attacker detonated explosives-laden car outside military headquarters.
Soldiers taken by surprise by coordinated attacks in heavy fog.
Yemeni security official says six suspected al-Qaida militants and two citizens fighting them were killed in separate clashes.
Israeli group aided in escape from political unrest in country.
