The UN Security Council has failed to condemn the deadly air raid on a migrant detention centre in the Libyan capital Tripoli amid global outrage over the attack that killed 44 people and wounded 130 others.

Earlier, the United Nations envoy to Libya, Ghassan Salame, condemned the air raid saying it “clearly could constitute a war crime”.

The attack in the early hours of Wednesday intensified concerns about the European Union’s policy of teaming up with Libyan militias to block refugees and migrants from crossing the Mediterranean Sea, which often leaves them at the mercy of brutal traffickers, or stranded in horrible conditions inside squalid detention centres near the front lines.

It could also lead to greater pressure on renegade military commander Khalifa Haftar, whose forces launched an offensive to seize the capital in April. The Tripoli-based UN-recognised Government of National Accord (GNA) blamed pro-Haftar forces of carrying out the attack on the detention camp.

According to the UN Support Mission in Libya, the air raid killed at least 44 people and wounded more than 130.

“The absurdity of this ongoing war today has led this odious bloody carnage to its most hideous and most tragic consequences,” it said in a statement.

UN Secretary-General Antonio Guterres called for an independent investigation of the “outrageous” bombing.

His spokesman Stephane Dujarric said the secretary-general condemns “this horrendous incident in the strongest terms” and wants to ensure the perpetrators of the attack are brought to justice.

Al Jazeera’s Rob Reynolds, reporting from Washington, DC, said that the UNSC met for more than three hours discussing the air attacks but they were unable to reach any conclusion on whether to take any action.

“It does not look like the UN is going to do anything beyond issuing condemnation which is quite sad given that what’s happening in Libya can set a very serious dangerous precedent globally,” said Hafed Al Ghwell from Johns Hopkins University.

Al Ghwell told Al Jazeera that the UN has failed to even condemn the aggression by [Haftar], who has been trying to take over the capital of a government that is recognised by itself.

“That’s a sign of a serious failure happening at the UN at the highest level. It can signal that every warlord in the world or a would-be warlord can get away with such an action.”

Meanwhile, air traffic was halted on Wednesday at Tripoli’s only functioning airport, Mitiga, after another air strike hit the facility, according to authorities. No further details were immediately available.

‘Horrific tragedy’

The detention centre, which is located next to a military camp in the eastern suburb of Tajoura, houses more than 600 people, but the part that was hit held some 150 male refugees and migrants from African countries such as Sudan, Eritrea and Somalia.

“This crime came after the statements of the air force commander of Haftar’s Libyan National Army [LNA], Mohamed Manfour and therefore it is he who bears its legal and moral responsibility,” GNA’s Interior Minister Fathi Bashagha told Alwasat state radio.

On Monday, Manfour said aerial bombardment would be stepped up because “traditional means” to “liberate Tripoli” had been exhausted, and urged residents to stay away from what he called “confrontation areas”.

However, LNA spokesman Ahmed al-Mesmari denied responsibility for the attack and also called on the UN to open an investigation. Mesmari blamed the carnage on Haftar’s rivals in the GNA.

“This operation is a terrorist operation carried out by the militias. We are targeting legitimate targets in Tripoli,” Mesmari said.

Al Jazeera’s Mahmoud Abdelwahed, reporting from Tripoli, said there were fears the death toll could rise as rescue teams were still searching for survivors to transfer them to medical centres on Wednesday.

“Migrants who survived the attack are in a state of panic worried about what will happen to them next following the destruction of the detention centre,” he said.

“Many of them were stranded in front of the detention centre until this morning. Others were taken to the medical centres.”

‘Urgent evacuation’

Haftar’s offensive threatens to plunge Libya into another bout of violence on the scale of the 2011 conflict that overthrew longtime leader Muammar Gaddafi and led to his death.

“This is a horrific tragedy that should never have happened,” Charlie Yaxley, spokesman for the Mediterranean and Africa at the United Nations High Commissioner for Refugees (UNHCR), told Al Jazeera from Geneva.

He added the UNHCR had warned of the dangers faced by the detainees at Tajoura some two months ago when another air raid damaged the centre’s roof and wounded two people.

“We called for an urgent evacuation then. They remained detained inside that centre and sadly people have paid the tragic price of that with their life last night,” Yaxley said.

Wounded migrants and refugees were taken to hospitals following the attack [Ismail Zitouny/Reuters]

Key departure point

Libya is a key departure point for migrants and refugees from Africa and Arab countries trying to reach Italy by boat, but many get picked up by the Libyan coastguard, which is supported by the European Union.

Detention centre officials blamed the raid on Haftar’s forces [Mahmud Turkia/AFP]

Thousands are being held in government-run detention centres in what human rights groups say are often inhuman conditions.

Tajoura, east of Tripoli’s centre, is home to several military camps of forces allied to the Tripoli-based GNA.

The LNA, which controls much of eastern and southern Libya, has failed to take Tripoli in three months of fighting and last week lost its main forward base in Garyan, which was taken back by Tripoli forces.

The African Union (AU) condemned the air raid and demanded those responsible be held accountable.

In a statement on Wednesday, AU Commission Chairman Moussa Faki Mahamat called for an “independent investigation to be conducted to ensure that those responsible for this horrific crime of innocent civilians be brought to account”.

Mahamat urged the international community to “redouble efforts” to bring the warring parties to the negotiating table.

The UN’s mission in Libya has said around 3,500 migrants and refugees held in detention centres near the combat zone are at risk.

Yaxley said a new policy was needed that would see an end to the return of refugees to the North African country.

“No refugee should be returned to Libya at this time,” he said, calling for a comprehensive review “that looks at the issues all across the routes the refugees and migrants are travelling”.

“We need to address this as a humanitarian issue with a regional approach that brings passengers to shores quickly and safely and shares responsibility for hosting them,” he said.