Accusations of responsibility for Monday evening’s bombing raid on Derna in which at least 15 civilians died, including 12 women and children, are being levelled at both the Libya National Army (LNA) and the Egyptian air force. The accusations come as the ambassadors of France, Italy the UK and US today joined the chorus of condemnation of the attack, while the Presidency Council has declared three days of national mourning.

The accusation that Field Marshal Khalifa Hafter and the LNA carried out the airstrikes has come from the president of the State Council, Abdulrahman Sewehli, as well as from the Justice and Construction Party (J&C).

Describing the killings as a political watershed, Sewehli accused the “eastern command” – in other words the LNA – of responsibility. He called on the UN Security Council to meet in emergency session to decide on action in accordance with UN Resolution 1973.

Likewise calling for the UN to take action, the J&C labelled Hafter and the LNA as terrorists, accusing them of war crimes for targeting unarmed civilians.

In Egypt, however, although the country’s foreign ministry yesterday condemned “in the strongest terms” the incident, the online newspaper Mada Masr reported that it had been told by an Egyptian government source that the airstrikes were carried out by the Egyptian air force. The reason, according to the source, was to pre-empt plans by militants in Derna to cross into Egypt and carry out terror attacks there.

The Derna Mujahideen Shoura Council had already accused the Egyptians of carrying out the raids.

There have been previous attacks by the Egyptian air force. Last May, Cairo announced that it had carried out airstrikes on Derna in collaboration with the LNA, hitting strategically important sites held by the DMSC. The attack was in retaliation for the massacre of 28 Christians in central Egypt’s Minya province. Cairo claimed that it had been organised with the help of militants based in Derna. The town was also bombed in 2015 by the Egyptians in revenge for the Islamic State beheadings in Sirte of 21 Christians, 20 of them Egyptians.

Just last week, Egyptian planes hit a convoy of eight vehicles crossing the border from Libya into Egypt and which the air force said were carrying weapons and ammunition for terrorists. The Egyptians apparently believe that arms originated from Derna.

Monday’s raid followed the 21 October attack by terrorists in Egypt’s Western Desert in which 16 police and conscripts were killed.

In today’s joint statement condemning the air strikes, the four ambassadors also condemned the torture and summary execution of 36 men whose bodies were found in Al-Abyar last week, insisting that anyone suspected of carrying out such executions and torture, or who failed to prevent them, be investigated and put in trial. They also said that their governments would pursue “at the international level” anyone involved in human rights crimes.

This is seen as referring to possible arrest warrants from the International Criminal Court.

Italian foreign minister Angelino Alfano had already issued his own statement condemning the attack and demanding that humanitarian organisations be allowed access to the town to deal with the wounded and “relieve the suffering of the people”.

In its condemnation of the killings, the Presidency Council has announced three days national mourning. The DMSC-dominated Derna local council had already declared three days of mourning.

The killings and the humanitarian situation in Derna as a result of the LNA blockade were meanwhile one of the main subjects in discussions today between PC head Faiez Serraj and UN deputy special envoy Maria Ribeiro who is also the UN’s humanitarian coordinator for Libya.

The number of casualties of Monday’s raid in which one or more private houses were hit, is still uncertain. While it is reported that at least fifteen people died, reports from Derna say that 20 civilians were killed and a further 23 wounded. Of the dead, all are said to have been children apart from two women and a man.