Boys gather near the wreckage of a car destroyed last year by a US drone air strike targeting suspected Al Qaeda militants in Azzan, of the southeastern Yemeni province of Shabwa, on February 3, 2013. Reuters/Khaled Abdullah Ali Al Mahdi "I was on my way to play football with my friends when the airstrike hit," Amin Ali al-Wisabi told VICE News, recounting the day when a CIA drone struck his hometown of Azzan in Yemen. "We had stopped to sit down and plan the match when all of a sudden an explosion hit a passing al-Qaeda car."

Recovering from his shock, 13-year-old Amin realized he had been hit by shrapnel. "Blood was pouring from my leg."

Next to Amin, his friend Hamza Khaled Baziyad lay unconscious. In total, five children aged between 10 and 14 were injured as they gathered close to the local mosque.

Though the number of people injured in covert US strikes is not officially recorded, they play a crucial role in the struggle for hearts and minds across Yemen's southern hinterland. Bystanders and family rushed the children to a local clinic, where Hamza awoke while shrapnel was extracted from his chest. All of the children survived.

The targeted car as it continues to burn following the CIA drone attack in Azzan on March 30, 2012. (Photo by Ayman al-Bariki)

Representatives of Ansar al-Sharia — al-Qaeda in the Arabian Peninsula's (AQAP) political wing — would later visit the children, bringing candy and 100,000 Yemeni riyals each (then worth $465). The militants also swore to take revenge on the families' behalf, tapping into the Yemeni tradition of blood feud.

Saleh Muhammed al-Sunna, a 55-year-old pedestrian on his way to Azzan's vegetable market, was just 15 meters (50 feet) from the targeted vehicle. The intensity of the blast tore his body to pieces. Days later Ansar al-Sharia gave his family 200,000 riyals.

"The deaths of innocent bystanders has a moral dimension but also a huge strategic dimension in cultures which have a very strong sense of honor," said British MP David Davis, chair of the UK's All-Party Parliamentary Group on Drones. "It will make the problem worse."

The Azzan strike, on March 30, 2012, is clear proof of the risk. "We were devastated by the news of Saleh's death," said Abdelhakim al-Hadad, al-Sunna's cousin. "We would have done anything to avenge his death. America and Britain are the ones who deprived our family of its breadwinner."

The ID card and portrait of Saleh Muhammed al-Sunna, who was killed by the drone strike while on his way to buy vegetables. Witnesses found his body in pieces. (Photo by Abdelhakim al-Hadad)

The target of the strike was Ahmed Said Saad, who five Azzan residents described to VICE News as a Syrian doctor and a member of Ansar al-Sharia. Documents from GCHQ, Britain's signals intelligence agency, leaked by Edward Snowden, described Saad using the codename "Khalid Usama," as part of a group of radical surgeons working for AQAP.

According to another account, Saad is believed to have worked with bomb maker Ibrahim al-Asiri to surgically implant undetectable explosives in would-be suicide bombers.

Al-Asiri had already experimented with inserting explosives into the anal cavity but found that the volume of explosives that could be held there struggled to project through the body. Instead he moved on to producing explosives to be placed in the potential suicide bomber's "love handles."

Earlier that day, Saad gave a talk seven miles down the road in the town of al-Houta in Shabwa governorate. As a VICE News investigation revealed, the doctor was found by an agent working for Britain's Secret Intelligence Service (SIS, also known as MI6) who tagged his vehicle, allowing it to be picked up by the Overhead program — a surveillance network run by the US, UK, and Australia integrating satellite imagery with digital and telephonic communications.

'They could've hit them on open road, away from a built-up area. Why didn't they do that?'

The Overhead program, of which GCHQ is a part, then informed the CIA, who sought corroboration of the target's location from officers at Yemen's National Security Bureau (NSB), who SIS agents were mentoring, before routing a drone to intercept the car. It is likely GCHQ was tracking Saad as part of the program, before passing on the information for the strike. As a former senior CIA official responsible for operations in Yemen explained: "The sharing there was very, very extensive... particularly with the Brits. There was very clear coordination and cooperation."

Ministry of Defence

Although Saad's 4x4 was in open ground on its short journey, the Reaper drone tracking his vehicle did not fire until the car entered Azzan, a town of approximately 10,000 people. The CIA drone unleashed a Hellfire missile as the vehicle passed by a vegetable market near a mosque in the western district of Azzan's inner town. The two militants were killed instantly.

The proximity of al-Sunna, only 15 meters from the blast, and the shrapnel injuries to five children in a populated area raise questions about the CIA's rules of engagement. US military documents leaked to The Intercept in 2015 show that one condition required before a strike is that there is a "low" risk of collateral damage, as determined by a pre-strike Collateral Damage Environment (CDE) assessment.

"CDE-Low," according to US rules of engagement guidelines, means that no civilian should be within the "kill radius" of the strike, which for a Hellfire missile is 15-20 meters from the point of detonation. The strike is deemed to be CDE-Low if civilians are within the "casualty radius," the area within which there is a risk of shrapnel injury. While the five children were within the casualty radius of the strike, al-Sunna was within the kill radius, suggesting that the CIA did not conform to the US military's rules of engagement.

The attack also raises questions in Britain about the legality of SIS' intelligence sharing, which was critical to the find-and-fix phase of Saad's assassination. UK rules of engagement require that there is no risk of collateral damage according to the pre-strike CDE, either within the kill or casualty radius of the strike.

"Where the British state knows the intelligence will lead to an assassination, we ought to be confident that it meets our own rules and guidelines, by which I mean laws," Davis, the UK MP, told VICE News.

SIS shared the targeting information because Saad's name was added to a shared kill list by President Barack Obama. At the time, the addition sparked debates within the US intelligence community. According to Daniel Klaidman, author of Kill or Capture, several US intelligence officials were skeptical of Saad's involvement in al-Asiri's work. There were also concerns about the implications of targeting doctors.

But as one former senior CIA official, responsible for operations in Yemen, told VICE News, al-Asiri was undoubtedly "among the most dangerous threats to Western nations." By extension that included his acolytes and, once Obama had ruled on Saad's fate, the CIA and SIS were cleared to engage.

That they eventually did so inside a densely populated town alarmed many of Azzan's residents. Mohsen Hassan Salem, who took his injured nephew Amin for treatment in the provincial capital of al-Mukalla some 140 miles away, told VICE News that "the family really struggled" to meet the $1,500 cost of treatment. "They could've hit them on open road, away from a built-up area. Why didn't they do that?"

Protesters loyal to the Shiite al-Houthi rebel group burn an effigy of a US aircraft during a demonstration to protest against what they say is US interference in Yemen, including drone strikes, after their weekly Friday prayers in the Old City of Sanaa on April 12, 2013. Reuters/Khaled Abdullah Ali Al Mahdi

Nearly a year after the strike, the CIA arranged for $50,000 in freshly minted dollar bills to be paid to al-Sunna's family via the NSB, Yemen's principal intelligence agency. But they never compensated the children. This is only the second publicized case of secret CIA condolence payments.

A spokesman for the White House's National Security Council told VICE News: "Although we will not comment on specific cases, were non-combatants killed or injured in a US strike, condolence or other ex gratia payments, such as solatia, may be available for those injured and the families of those killed."

But the CIA's gesture was likely too little too late. By then AQAP had already twice visited the injured children to pay condolences, bringing 50,000 riyals on each occasion and promising revenge on their behalf. The CIA's cash delivery was not accompanied by any recognition of its mistake or apology. The NSB official who handed al-Sunna's family representative the money suggested but never conceded that the money had come from "the Americans."

'It was as if a sheep had been slaughtered, nothing more'

Al-Hadad, authorized to represent the family, said that in exchange for receiving the cash, the NSB official demanded he bring a signed declaration from the family stating that they would forfeit any legal recourse. The encounter with the NSB was cold, he said. "It was as if a sheep had been slaughtered, nothing more."

The Yemeni government has long struggled to maintain a strong presence outside of Sanaa, and such interactions engendered hostility among the local population, making them less willing to provide information about al-Qaeda, and even sympathize with the jihadist cause. Since 2011, Azzan has been regularly occupied by AQAP militants, who once again took the town last February.

Professor Jillian Schwedler, of City University of New York, recently wrote that historically Yemen's Islamists saw no place for jihadists in the country's politics. But the secret war in Yemen, now in its 15th year, helped change that. "For al-Qaeda, the drone program is a gift from the heavens. Its recruiting narrative exploits common misperceptions of American omnipotence, offering an alternative route to justice and empowerment," she noted.

The British government has never publicly admitted involvement in the US' covert war in Yemen. Moreover, in 2013, UK Ambassador to Yemen Jane Marriott categorically stated: "We don't support any form of extrajudicial killing." But, as a VICE News investigation revealed, British SIS officers and seconded military personnel provided systematic and sustained support for the CIA strikes in Yemen. And in Saad's case, British intelligence was crucial to his assassination.

VICE News put its findings to the CIA, GCHQ, and the British Foreign and Commonwealth Office, which represents SIS, but all declined to comment.

Letta Tayler, senior counterterrorism researcher at Human Rights Watch, commented: "When AQAP does a better job than the US government at providing redress for civilian deaths in US drone strikes, the Obama administration should realize it has a serious problem."

"These allegations raise serious questions about the role the UK is playing in Washington's legally dubious drone program, The UK should immediately make public any role it played in US drone strikes in Yemen, and explain the basis for these actions under international law."

Additional reporting by Mohyeddin al-Shawtari.