At least five civilians have died in a Saudi-led coalition air strike in Yemen, eyewitnesses have said, as calls at the UN grow for an independent body to investigate possible war crimes being committed in Yemen’s civil war.

Fighter jets attacked a Houthi rebel-controlled checkpoint outside the capital of Sanaa on Wednesday morning, killing five civilians sitting in a taxi and two armed personnel at the site, witnesses said.

Rebel officials said that the strike hit an oil tanker waiting at the checkpoint, which exploded – as did a nearby petrol station, which caught fire and complicated rescue efforts. They put the death toll at 13, adding that the victims had all been burnt alive.

Michael Fallon claims Saudi Arabia is only 'defending itself' when attacking Yemen

There was no immediate comment from the coalition on the strike in Masajed, about 10 km (six miles) west of the city.

The civilian deaths come on top of last week’s bombings of a hotel and civilian three-storey building which combined killed approximately 60 people.

Riyadh and its allies have extensively bombed Houthi rebels in charge of Yemen’s capital and north since March 2015 at the request of the exiled, internationally recognised president, Abdrabbuh Mansour Hadi.

The situation in Yemen Show all 14 1 /14 The situation in Yemen The situation in Yemen Houthi supporters trample on a US flag during a gathering mobilizing more fighters into several Yemeni battlefronts, in Sana'a, Yemen EPA The situation in Yemen People carry the coffins of men, who were killed in the recent Saudi-led airstrikes during their funeral, in the Old City of Sanaa, Yemen AP The situation in Yemen Pro-government fighters give food to Yemeni children on the road leading to the southwestern port city of Mokha. Yemeni rebels are putting up fierce resistance in a key Red Sea port city where they are encircled by pro-government force Getty Images The situation in Yemen A Yemeni stands in front of a graffiti protesting US military operations in war-affected Yemen, in Sana'a, Yemen. According to reports, US Special Forces troops allegedly disembarked from US helicopters in the Yemeni town of Yakla and attacked several houses belonging to members of the terrorist group Al-Qaeda, killing three high-ranking Al-Qaeda members and nine civilians, six women and three children. One American serviceman has been killed and three injured in the attack EPA The situation in Yemen US Special Forces troops allegedly disembarked from US helicopters in the Yemeni town of Yakla and attacked several houses belonging to members of the terrorist group Al-Qaeda, killing three high-ranking Al-Qaeda members and nine civilians, six women and three children. One American serviceman has been killed and three injured in the attack EPA The situation in Yemen A Yemeni female fighter supporting the Shiite Huthi rebels, and carrying weapons used for ceremonial purposes, takes part in an anti-Saudi rally in the capital Sanaa Getty Images The situation in Yemen Yemeni female fighters supporting the Shiite Huthi rebels, and carrying weapons used for ceremonial purposes, take part in an anti-Saudi rally in the capital Sanaa Getty Images The situation in Yemen A boy shouts slogans next to pro-Houthi fighters, who have been injured during recent fighting, during a rally held to honour those injured or maimed while fighting in Houthi ranks in Sanaa, Yemen Reuters The situation in Yemen Balls of fire and smoke rise from a Houthi-held military camp following alleged Saudi-led airstrikes, in Sana'a, Yemen EPA The situation in Yemen Yemenis search under the rubble of damaged houses following reported Saudi-led coalition air strikes on the outskirts of the Yemeni capital Sanaa Getty Images The situation in Yemen A Yemeni boy looks on as Yemenis search under the rubble of damaged houses following reported Saudi-led coalition air strikes on the outskirts of the Yemeni capital Sanaa Getty The situation in Yemen A Yemeni boy sits amidst the rubble of damaged houses following reported Saudi-led coalition air strikes on the outskirts of the Yemeni capital Sanaa AFP/Getty The situation in Yemen Marine One with US President Donald Trump flies with a decoy and support helicopters to Dover Air Force Base in Dover, Delaware, for the dignified transfer of Navy Seal Chief Petty Officer William 'Ryan' Owens who was killed in Yemen Getty Images The situation in Yemen US President Donald Trump aboard the Marine One to greet the remains of a US military commando killed during a raid on the al Qaeda militant group in southern Yemen on Sunday, at Dover Air Force Base, Delaware, US Reuters

The campaign has been repeatedly criticised for causing an excessive loss of civilian life.

Saudi blockades on Yemen’s ports and airspace have also been blamed for causing the current famine facing the country’s 22-million-strong population as well as the worst cholera outbreak in modern history, which has infected 500,000 people.

On Tuesday, Human Rights Watch (HRW) and 56 other international non-governmental organisations urged the United Nations to establish an international body to investigate abuses they say may amount to war crimes committed by all the warring parties in Yemen.

Such a panel should “begin chipping away at the impunity that has been a central facet of Yemen's war,” HRW’S Geneva director John Fisher said in an open letter to the UN’s human rights council.

A report authored by several international aid agencies released earlier this month said Yemen suffered more air strikes in the first half of this year than in the whole of 2016, increasing the number of civilian deaths and forcing more people to flee their homes.

Western governments have also faced criticism for their role in the war: arms sold to Saudi Arabia are destined for use in the Yemeni war, rights groups say.

Officials within former US President Barack Obama’s administration were worried the sales could amount to complicity in war crimes.