Libyan military forces fighting for control of the capital Tripoli have launched airstrikes on each other, escalating a battle that has raged since Thursday. The United States said Sunday it would temporarily withdraw its troops from Libya because of the security situation on the ground. Libyan military commanders and troops advancing toward the capital Tripoli as they clash with rival militias, a senior military official said Sunday as they approached them.

The government in Tripoli blamed the air strikes on the self-proclaimed Libyan National Army, led by Khalifa Haftar, and called for the establishment of an investigative commission. Hifter's forces also said two ambulances in southwest Libya that had been attacked by militias allied with Tripoli had been targeted. Al-Majei confirmed that the Libyan army had entered the town of Zawiya, about 100 kilometers (100 miles) south of Tripoli.

The department suspended U.S. embassy operations in Tripoli on March 1, 2015, due to the ongoing conflict in Libya. The embassy was temporarily transferred to the IRC in March 2015, where it operates under the auspices of the United Nations High Commissioner for Refugees (UNHCR) to facilitate the transfer of humanitarian aid and assistance to Libya and other countries in the region. IRC is the only international humanitarian organisation in North Africa and the Middle East and one of only a handful of such organisations in the world.

Libyan coast east of Tripoli, The Wheelus Air Base to the east has been used by the United States Strategic Air Command since the 1950s to support nuclear-capable aircraft. Libya has closed US and British military bases, and NATO troops have bombed many of the already derelict sites.

American troops and diplomatic personnel continue to work in the country to help the Libyan government maintain its shaky grip on power. Although Washington and Tripoli do not have diplomatic relations and relations between Britain and Libya are strained, their intelligence services have been in contact for years.

Haftar declared a no-fly zone over the western half of Libya last week after his forces were attacked by the government's air force. The clashes appeared to have done little to slow Haftar's advance on Tripoli, but they did allow Tripoli's troops to retake parts of the Libyan capital previously captured by Hifter's side.

Libya has been embroiled in violence since NATO airstrikes toppled and killed Gaddafi in 2011, and fighting in Tripoli threatens to plunge Libya back into the chaos of the 2011 conflict that toppled longtime dictator Gaddafi and led to his death. The United States has had a presence in Libya for decades, but has played a limited role, helping to lead the US military campaign to topple former Libyan leader Muammar Gaddafi after 2011. In Libya, the physical war is accompanied by the intensity of the struggle on satellite television and social media, where Libyan trolls and provocateurs have ignited a battle for control of satellite television in eastern Libya - where Haftar's rise began - and in the west, including Tripoli.

Governance in Libya remains divided between two entities involved in armed conflict: the internationally recognised GNA, based in Tripoli, and the rival transitional government from eastern Libya, which is affiliated to LAAF.

Both sides regard the war as existential and have rejected calls for an unconditional ceasefire. Haftar wants a capital under his control and has rejected a ceasefire; he wants his troops to withdraw from eastern Libya, but Tripoli rejects any project that does not involve the return of its troops to the capital, Tripoli. There is no train network in Libya yet, although Libya plans to introduce connections to the east and west of the country. Both sides have rejected calls for unconditional ceasefires, with the prospect that neither Tripoli nor Benghazi would accept monitoring.

Italy has also sought to quarantine the flow of people into Libya by helping Tripoli pay militias, which directly strengthens its power. Italy's energy interests are not alone in having a vested interest in shaping a turbulent Libya. Libya descended into chaos when a NATO-backed uprising toppled longtime dictator Muammar Gaddafi in 2011, who was later killed. Since his fall, Libya has been rocked by conflicts that have splintered into a series of civil wars, civil wars and unrest.

Haftar, born in 1943, allied himself with a young captain named Muammar Gaddafi after the overthrow of the Libyan monarchy in 1969. In 2011, the 75-year-old general, who had once served under Gaddafi, returned to Libya to support the revolution against the dictator.

Hafar marched toward the capital Tripoli and set off for the Fezzan region, a region of about 1.5 million people. He was asked to lay the foundations for the army to liberate two more cities after the recapture of Tripoli airport.

The implicit message is that only Haftar's eastern-based coalition is a safe and natural fit to govern Libya's true population. The UN Assistance Mission in Libya welcomed the statement but called for the expulsion of foreign troops and mercenaries from Libya, calling Tripoli its home, even though it has largely accumulated power in eastern and southern Libya.