An apparent airstrike launched by a warlord backed by the west’s Arab allies hit a migrant-holding facility in a suburb of the Libyan capital early on Wednesday, killing as many as 80 civilians and injuring scores more.

The attack in Tajoura, a coastal town east of Tripoli, left behind body parts and charred clothing mangled with concrete and steel girders, according to photos and video posted online. Women and children were among the dead. Hospitals in and around the capital were flooded with badly wounded victims, often dazed and unable to speak. Most speak sub-Saharan languages and little Arabic or English, and have struggled to communicate with medical staff.

“I arrived to the centre in east Tripoli at around 1am, it had been hit severely. It was dark and the air was filled with smoke and the smell of blood and burnt meat,” Ameen Hashimi, media adviser to the country’s Ministry of Health, told The Independent.

“There was blood and body parts all over the place, and some people were being rescued from under the fallen building by the time I left.”

The Tripoli-based government condemned what it described as a “massacre” and demanded an international investigation.

“The Presidency Council of the Government of National Accord condemns in the strongest terms this terrible crime, in which planes belonging to the war criminal Khalifa Haftar targeted a migrant shelter in Tajoura, killing and injuring dozens,” its statement said.

Turkey, a major backer of the Tripoli government, called the attack a “crime against humanity,” in a foreign ministry statement.

“We expect the international community to act on this issue immediately,” it said.

Around 600 people were being held in the facility, known as the al-Daman complex, one of a number of de facto prisons where migrants attempting to cross into Europe are held after being picked up at sea. The facility is located in a former industrial zone that includes a pro-Tripoli armed group in charge of countering migration. Death estimates varied with tallies ranging from 40 killed to as many as twice that number, along with up to 100 injured, according to the Sadeq Institute, a think tank focused on Libya.

Western Libya is locked in a three-month battle for control of the capital, pitting the forces of Libyan warlord Khalifa Haftar – backed by Egypt, the UAE and Saudi Arabia – against the United Nations-brokered authority in Tripoli. At least 739 people have died in the conflict.

Libya airstrike: Migrant detention centre hit in airstrike, killing 60 Show all 9 1 /9 Libya airstrike: Migrant detention centre hit in airstrike, killing 60 Libya airstrike: Migrant detention centre hit in airstrike, killing 60 Migrants carry the remains of their belongings from among rubble at a detention centre for African migrants that was hit by an airstrike in the Tajoura suburb of Libyan capital Tripoli on July 2 Reuters Libya airstrike: Migrant detention centre hit in airstrike, killing 60 Security and emergency responders work at the site of an airstrike that hit a detention centre for African migrants near Tripoli, Libya on June 2 Reuters Libya airstrike: Migrant detention centre hit in airstrike, killing 60 Security and emergency responders work at the site of an airstrike that hit a detention centre for African migrants near Tripoli, Libya on June 2 Reuters Libya airstrike: Migrant detention centre hit in airstrike, killing 60 The point of impact of a bomb that was dropped on a detention centre for African migrants near Tripoli, Libya on June 2 AFP/Getty Libya airstrike: Migrant detention centre hit in airstrike, killing 60 Blood stains are seen among debris following an airstrike that hit a detention centre for African migrants near Tripoli, Libya on June 2 Reuters Libya airstrike: Migrant detention centre hit in airstrike, killing 60 A woman picks up clothes among rubble at a detention centre for African migrants that was hit by an airstrike in the Tajoura suburb of Libyan capital Tripoli on July 2 Reuters Libya airstrike: Migrant detention centre hit in airstrike, killing 60 Migrants gather outside following an airstrike on the detention centre in the Tajoura suburb of Libyan capital Tripoli on July 2 AFP/Getty Libya airstrike: Migrant detention centre hit in airstrike, killing 60 A man carries his belongings from among rubble at a detention centre for African migrants that was hit by an airstrike in the Tajoura suburb of Libyan capital Tripoli on July 2 Reuters Libya airstrike: Migrant detention centre hit in airstrike, killing 60 Migrants sit together with their remaining belongings in the yard of the detention centre that was hit by an airstrike in the Libyan capital of Tripoli on July 2 Reuters

The refugees caught in the crossfire are part of a years-long surge of migrants attempting to flee drought, economic malaise, and war in Africa and the Middle East to settle in Europe.

The UN has repeatedly described war-torn Libya as unsafe for migrants and urged Libyan and European authorities not to settle refugees there. But Italy and other EU countries continue to fund the Libyan coast guard and encourage its efforts to keep refugees from crossing the Mediterranean.

The office of the United Nations High Commissioner for Refugees wrote in a tweet that it was “extremely concerned about news of airstrikes targeting Tajoura detention centre”, adding that “civilians should never be targeted”.

“What is needed now is not empty condemnation but the urgent and immediate evacuation of all refugees and migrants held in detentions centres out of Libya,” said Prince Alfani, Medecins Sans Frontieres’ medical coordinator for Libya.

“Today, inaction and complacency have needlessly cost the lives of more vulnerable refugees and migrants.”

Malek Sharif, spokesperson for Mr Haftar, said the allegations that his forces were behind the attack were “incorrect”.

“The LNA has no air operations,” he told The Independent, declining to elaborate.

There is no evidence to suggest Mr Haftar’s Libyan National Army (LNA) forces targeted the facility. But just hours before the facility was hit LNA spokesperson Colonel Ahmed Mismari announced ongoing airstrikes targeting Tajoura and other cities along the Tripoli front lines.

In the past, the LNA, which has deployed fighter jets provided by the United Arab Emirates and Egypt, has accused the Tripoli-based Government of National Accord (GNA) of using civilians as “human shields”.

The attack, described as two airstrikes on the facility, comes days after Mr Haftar promised heightened aggression following the loss of the strategic city of Gharyan to GNA forces last week.

Despite a UN arms embargo, both sides in the conflict are receiving military equipment from abroad.

GNA forces attempting to seize the city reportedly found advanced American anti-tank rockets sold by the US to the UAE. The UAE denied the weapons were theirs.

Last month Turkish president Recep Tayyip Erdogan acknowledged to international journalists that Turkey was sending military equipment to assist pro-GNA forces.

Rights group Amnesty International had warned earlier on Wednesday about the devastating effects the violation of the UN embargo were having on civilians.

“The UN arms embargo is meant to protect civilians in Libya. But Jordan, the United Arab Emirates and Turkey, among others, are blatantly flouting it by providing sophisticated armoured vehicles, drones, guided missiles and other weapons,” said Magdalena Mughrabi, deputy Middle East and North Africa director at Amnesty.

“The UN Security Council must urgently take steps to enforce the embargo, and the warring parties must respect international humanitarian law and stop recklessly endangering civilians.”

Jalel Harchaoui, North Africa specialist at Clingendael, a Dutch think tank, suggested that supporters of Mr Haftar would flood social media, obfuscating culpability for the bombing out of fear of alienating nervous supporters such as France and Russia.

“I am sure that the pro-Haftar propagandists have a point when they blame the Misratans for storing weapons near the migrants,” he said. “But I am old-school: the horrendous massacre is also attributable to those that ordered the airstrike.”

The attack poses a challenge for western countries such as the US, UK, and France, who formally support the UN-backed government while at the same backing the Arab autocracies that are Mr Haftar’s pillars of support. “If they remain silent on Haftar, it opens the way for another type of war,” added Mr Harchaoui. “It would send him a green light that he can kill much more.”