Tripoli, Libya (CNN) -- Heavy fighting continued Monday in Benghazi between Libyan army forces and an Islamist militant group the United States blames for the attack last year on its diplomatic mission that killed four Americans, including Ambassador Christopher Stevens. LANA, Libya's state news agency, reported that at least six soldiers and one civilian were killed and 39 people were injured, most of them soldiers, in the clashes Sunday between the military and the group Ansar al-Sharia. On Monday, the Libyan government said that at least nine people were killed and 49 injured. A senior Libyan military official in the city, speaking to CNN on condition of anonymity for security reasons, said heavy fighting continued Monday morning as troops engaged members of the group in different parts of Benghazi.
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NEW: Clashes that erupted Sunday night in eastern Benghazi continue into Monday
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Government is engaging fighters from Ansar al-Sharia, which the U.S. says attacked its consulate
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"This is really the heaviest fighting" since the revolution, a resident says
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A Libyan military official says forces are responding after an attack on army members
Over the past year, there has been a significant deterioration in the security situation in @placeholder, which is Libya's second-largest city and the cradle of the 2011 revolution.