The UN human rights chief on Friday condemned "international indifference" in the face of mounting deaths in Syria, warning that those responsible for air strikes targeting civilians could be charged with war crimes.

Since late April, the Syrian regime and Russia have stepped up deadly raids on the Idlib region of three million people, a jihadist-held bastion in the country's northwest.

United Nations High Commissioner for Human Rights Michelle Bachelet said she was alarmed at "the apparent international indifference to the rising civilian death toll caused by a succession of airstrikes in Idlib."

Bachelet stressed that medical facilities, schools, markets and other clear civilian targets have been hit.

"These are civilian objects, and it seems highly unlikely, given the persistent pattern of such attacks, that they are all being hit by accident," she said in a statement.

"Intentional attacks against civilians are war crimes, and those who have ordered them or carried them out are criminally responsible for their actions."

More than 730 civilians have been killed in Idlib in air strikes and ground-to-ground fire by the Damascus government and its allies since late April, according to the Syrian Observatory of Human Rights monitoring group.

Syria's opposition has condemned the bombardment as "genocide", while aid groups have branded the carnage in Idlib the latest "nightmare" in the eight-year conflict.

Bachelet said that even as "airstrikes kill and maim significant numbers of civilians several times a week" the international "response seems to be a collective shrug, with the Security Council paralysed."

"This is a failure of leadership by the world's most powerful nations," the rights chief added.

Top UN officials have repeatedly condemned the Security Council's inaction on Syria, with several measures vetoed Damascus ally Russia.

Syria's war has killed more than 370,000 people and displaced millions since it started in 2011 with a brutal crackdown on protests against President Bashar al-Assad's regime.

Five doctors killed in Libya air raid: ministry
Tripoli (AFP) July 28, 2019 –

Five doctors were killed in an air strike by forces of Libyan strongman Khalifa Haftar on a field hospital near the capital, the health ministry of the UN-recognised government said.

Haftar's self-styled Libyan National Army launched an offensive in April to try to wrest Tripoli from forces of the Government of National Accord which is based in the capital.

Pro-GNA forces have weathered the initial onslaught and since then fighting has remained deadlocked on the outskirts of the city, with both sides resorting to air strikes.

"The field hospital located on the airport road (south of Tripoli) was hit by an air raid. Five doctors were killed and seven other people, including rescuers, wounded," health ministry spokesman Lamine al-Hashemi said.

The strike occurred on Saturday and was carried out by "a Haftar warplane", he said.

"It was a direct hit against the hospital which was packed with medical teams," Hashemi added.

There was no immediate confirmation or denial of responsibility from Haftar's forces.

The attack was the third to target a hospital south of the capital.

On July 16 three doctors and a paramedic were wounded in a strike on the Swani hospital near the capital, the second time it was targeted.

The World Health Organization and rights groups have repeatedly called on both sides in the conflict to spare medical personnel, clinics and hospitals.

The fighting since April has left nearly 1,100 people dead and wounded more than 5,750, according to the WHO. More than 100,000 civilians have fled their homes.