THE UK is “among the least transparent” countries when investigating civilian deaths caused by its air strikes in the Middle East, a tribunal has heard.

In an eight-year bombing campaign against so-called Islamic State (IS) in Syria and Iraq as part of a US-led coalition, the UK Government claimed only one civilian was killed by the RAF.

But not-for-profit company Airwars has called for more transparency after the UK Government refused to release documents about the civilian fatality on the grounds that it would threaten national security.

The company, which “tracks, assesses, archives and investigates civilian harm claims in conflict-affected nations”, claims similar documents have already been released by the US government, which claimed responsibility for the deaths of more than 1,000 civilians in the same period.

The civilian killed in an RAF air strike died on March 26, 2018 in eastern Syria when they were riding on a motorbike, the government said.

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At a tribunal in central London on Wednesday, Airwars appealed against a decision by the Ministry of Defence and the Information Commissioner not to release documents related to the incident, describing their disclosure as “vital for the sake of basic military transparency”.

Joe Dyke, head of investigations at Airwars, first requested the documents in 2018.

He told the tribunal: “The documents we have requested are related to the one civilian death the UK Government has admitted in the eight years of its bombing campaign in Iraq and Syria.

“We as an organisation reviewed each of the policies of individual members of the coalition in terms of transparency and accountability.

“We consistently ranked the UK as one of the most transparent when it came to what they were striking and when.

“It was among the worst regarding the consequences of those incidents – in particular civilian harm.

“They would not go a step beyond and look at whether there was civilian harm from those actions.”

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Speaking before the tribunal, Emily Tripp, director at Airwars, said: “This tribunal is vital for the sake of basic military transparency.

“We still have no understanding as to how the UK military assesses whether or not their actions harmed civilians.

“The government insists that even a minimal level of transparency and openness would threaten national security.

“Without such transparency, there is no legitimacy to the Ministry of Defence’s claim that it only killed one civilian in the war against Isis (another term for IS) – which erodes public trust in our military institutions.”

When questioned by Will Perry, who represented Dyke, Alexander Oliver, a senior civil servant at the Ministry of Defence, admitted he was unaware of the burden of proof used by the government to determine whether a civilian had been killed in an air strike.

He insisted that the UK was not an “outlier” in its approach to investigating and publishing civilian casualties.

The two-day tribunal continues.