A member of the Libyan army fires at fighters from the armed group Ansar al-Sharia during a clash in the Ras Obeida area of Benghazi on Nov. 25, 2013. Esam Omran Al-Fetori/Reuters

Clashes between Libyan troops and an armed group in the eastern city of Benghazi have killed at least nine people and wounded at least 47 during a military operation, the Interior Ministry said.

The Libyan army on Monday declared a state of alert in Benghazi and summoned all troops to report for duty after a battle with Ansar al-Sharia fighters erupted.

Gunfire and explosions could be heard and thick smoke rose from the Ras Obeida area of the city. The army ordered residents to stay off the streets, witnesses told the AFP news agency.

Fighting broke out when an army special forces unit chased a suspect into an area where Ansar al-Sharia operates its own checkpoints, city security officials said. the group was blamed for the attack on the U.S. consulate in Benghazi a year ago when Ambassador Christopher Stevens and three other Americans were killed.

Rival militia groups withdrew from Tripoli last week after clashes killed more than 40 people when protesters marched to one of the fighters' bases to demand they leave the capital.