Fierce fighting as Haftar's forces close in on final Benghazi holdout

East Libyan forces battled to advance into a final area of Benghazi controlled by their opponents on Tuesday, clearing mines and roadblocks and targeting snipers with cover from tank rounds.

Khalifa Haftar's self-styled Libyan National Army (LNA) said it is close to concluding a three-year campaign for control of Libya's second city, having surrounded rival fighters on a 2km strip of the seafront district Sabri.

The campaign has been halting, with the LNA suffering high casualties even after gaining the upper hand early last year.

A medical source said at least 17 troops had been killed and at least 50 wounded in fighting since Monday. The LNA said it had killed 19 of its opponents.

"The special forces and supporting units from the army advanced today and tightened the grip on the terrorist groups on the Sabri front, gaining control over important sites," said special forces spokesman Milad al-Zawi. He said one of the sites was a building that contained a large number of snipers.

Parts of Benghazi have been left in ruins since Haftar launched his "Dignity Operation" against militants and other opponents in May 2014.

Many of the buildings in Sabri and the neighbouring historic neighbourhood of Souq al-Hout have been wrecked by street fighting, shelling and air strikes. Much of the area was heavily mined.

Three years ago, Libya split into two broad and shifting rival alliances based in the east and west of the country, loyal to competing governments, worsening the turmoil that followed a 2011 uprising that ousted Muammar Gaddafi.

Haftar's LNA has gained ground in Benghazi and other parts of eastern and southern Libya while rejecting a United Nations-backed government that arrived in the capital, Tripoli, in March 2016.

Meanwhile, two women and two girls were killed late on Tuesday when a shell landed on a beach near Mitiga airport in Tripoli, officials said.

The shell also wounded 15 people, hospital official Mohamed Ben Khalil told Libya Al-Ahrar channel. Pictures posted on social media showed plastic furniture strewn on the sand under strings of outdoor lights.

"The casualties are the result of clashes on Tuesday between a security force and outlaws who fired a shell that fell on a beach in front of Mitiga airport," Abdulsalam Ashour, a deputy interior minister in Libya's UN-backed government, told Al-Ahrar.

Other reports said the shell was fired during a revenge attack against one of the capital's many armed factions.

Tripoli is home to a patchwork of armed groups, some of which share control of Mitiga and the surrounding area. They occasionally clash in turf wars and localised disputes.

The beach lies across the other side of a coastal road from the airport in central Tripoli. It is popular with families trying to escape the heat on summer evenings.