By Ayman al-Warfalli
BENGHAZI, Libya, Jan 18 (Reuters) - About 600 people have been killed in three months of heavy fighting between Libyan pro-government forces and Islamist groups in Libya's second-largest city Benghazi, medical staff said on Sunday.
Backed by forces led by a former general, army special forces in mid-October launched an offensive against Islamists in Benghazi, expelling them from the airport area and from several camps the army had lost during the summer.
The fighting is part of a wider struggle in the oil producer where two governments and parliaments, allied to armed groups, are vying for control almost four year after the ousting of long-time ruler Muammar Gaddafi.
For two months the army has been trying to take the port area and two other districts where pro-government forces say fighters from the Islamist group of Ansar al-Sharia are holed up. The port has had to close.
Since the start of January, 34 people have been killed, most of them soldiers, and 23 wounded, hospital medics said.
"The total death toll is around 600," one medic said, asking not to be named. One hospital had 71 bodies in its morgue which had not been claimed by relatives, he said.
A Reuters reporter taken on tour by the army saw most parts of the city were controlled by special forces and allies loyal to former general Khalifa Haftar. Some districts had suffered heavy destruction from aircraft and artillery fire.
"We control 90 percent of the city," said Mohamed El Hejazi, spokesman for Haftar and the army.
Haftar have been using war planes to bomb Islamists in Benghazi. His opponents say he is backed by Egypt which is worried about the spread of militants. Haftar and Cairo deny this though analysts.
The army in the east is loyal to Prime Minister Abdullah al-Thinni who was forced to leave Tripoli in August for the eastern city of Bayda when a group called Libya Dawn seized the capital.
The new rulers in Tripoli set up their own government and parliament, but these have not been recognized by the United Nations. Both sides fight each other on several fronts.
Libya has failed to build up a national army and efficient state institutions since Gaddafi's ousting as the country is effectively run by former rebel brigades who use their weapons to fight for control.
Thinni is accusing Libya Dawn of relying on Islamist armed groups but has allied himself with Haftar, a Gaddafi-era officer commanding his own irregular forces.
Haftar's forces have now become part of the official army in the east, a move analysts say might complicate building up state institutions as his own political goals are unclear.
In a sign that Haftar's officers are increasingly dominating the army in the east, the House of Representatives appointed his air force commander Saqer al-Joroushi as the army's official air force head, he and lawmakers told Reuters. (Writing by Ulf Laessing; Editing by Jon Boyle)