TRIPOLI, Libya (AP) -- Gunmen attacked a security forces headquarters in Libya's eastern city of Benghazi early Friday, killing nine people and wounding 24, authorities said, blaming an Islamic extremist group allegedly behind the attack of a U.S. diplomatic post there.
A security official said the attack started when dozens of gunmen opened fire with machine guns and mortars. The onslaught lasted for an hour, with the fighting heard miles away.
Libyan commandos later arrived and fought the attackers, though the official said they suffered heavy casualties. A statement issued by the interim government and read by Cabinet spokesman Ahmed al-Amin put the death toll at nine people. Milad al-Zowi, a commando spokesman, said the dead were six army commandos and three police officers. Al-Zowi said that three soldiers and a police officer were missing after the battle.
A local hospital official said some of the slain troops were badly butchered, with some corpses burned.
The official said his hospital treated 24 people wounded in the fighting, with most suffering gunshot wounds to the chest and the abdomen. Some were in critical condition, he said.
The government said a number of militants were killed, while others were wounded and arrested. The statement did not elaborate.
Attackers likely tried to get their hands on a car loaded with weapons and ammunition that the security forces had confiscated the previous night, authorities added. A security official at the Benghazi headquarters, Gamal al-Amami, said the driver of the vehicle belonged to the Libya Shield militia.
The hospital official and security official spoke on condition of anonymity because they were not authorized to speak to journalists.
The government's statement blamed Ansar al-Shariah, a hard-line Islamist militia, for Friday's attack, along with other "criminal groups."
The government condemned the attack and said they will not accept "the presence of armed and illegal terrorist groups."
Ansar al-Shariah is blamed for the attack on the U.S. diplomatic mission that killed U.S. Ambassador Chris Stevens and three other Americans on Sept. 11, 2012.
In January, the U.S. State Department designated the two branches of the Ansar al-Shariah in Libya and a third branch in Tunisia as foreign terrorist organizations.
Benghazi, the birthplace of the 2011 uprising that led to the downfall of longtime dictator Moammar Gadhafi, has witnessed a series of attacks, targeted killings and bombings, mostly striking soldiers and police officers who served under the ousted ruler.
Libya has seen a severe deterioration in security and the government has depended on unruly militias in the absence of a strong police force or a unified military.
On Tuesday, a car bomb exploded in front of a military compound in Benghazi, killing two soldiers and wounding two. Later Friday, a car bomb killed a soldier driving his vehicle in Benghazi, officials said.
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