A rebel spokesman said that the prime minister, Mahmoud Jibril, the only member of the cabinet who kept his job, would have to present a new slate of cabinet members to the rebel legislative body, the Transitional National Council, for approval in the coming days. The cabinet was dissolved, the spokesman said, “for improper administrative procedures” that led to the arrest and subsequent killing of the military leader, Gen. Abdul Fattah Younes, a former top Libyan commander who defected to the rebel side.

The move left the rebels without several of its leaders — including the ministers of defense, finance, interior and justice — as they try to fight a three-front war, run dozens of cities under their control and rein in armed militias that have multiplied since the February uprising.