SECRET documents have revealed the UK is complicit in the controversial covert ‘drone war’ being carried out by the US, it has been claimed.

Classified documents from US whistleblower Edward Snowden have provided documentary evidence for the first time of the role of a American spy base within the UK.

Programmes to pinpoint the locations of terrorist suspects for ‘targeted killing’ drone strikes by tracking where they access the internet, were developed at RAF Menwith Hill in North Yorkshire, which largely staffed by staff from the US National Security Agency (NSA).

The US drone strikes have provoked huge controversy due to the secrecy surrounding the operations and because they have taken place in countries such as Pakistan, Yemen and Somalia - nations with which the US is not at war.

Ryan Gallagher, a journalist with online investigative magazine The Intercept, which obtained the documents, said they had revealed how the programmes with names such as Ghosthunter and Ghostwolf were pioneered from Menwith Hill.

He said: “There obviously a very uniquely British role here that has never really been understood or disclosed before.

“What this really shines a light on is that there has been more of a British role through the base on our territory that people didn’t know about.

“Technically speaking it is a US base on British territory, but that doesn’t exempt it from British laws and British policies.

“It is widely considered that drone strikes in places like Yemen outside of war zones constitute breaches of international law.

“If the British government is involved in this through these very sophisticated surveillance programmes being operated on British soil, then there are obviously some very serious questions to be asked about that.”

The documents reveal how Ghosthunter was developed in 2006 to locate targets when they log onto the internet, which enabled a “significant number of capture-kill operations against terrorists”.

Another internal NSA report, shows how a new initiative was launched at Menwith Hill in 2010 to identify targets at 40 different internet cafes in Yemen. It was linked to a programme called Ghostwolf to capture or eliminate “key nodes” in terrorist networks.

The RAF website states Menwith Hill is owned by the Ministry of Defence (MoD) and made available to the US Department of Defense.

It states Government ministers are fully briefed on activities carried out there "as a matter of course".

Gallagher raised concerns over secrecy surrounding the UK’s involvement, pointing out it had never been open to public scrutiny or debate.

“Obviously we understand that some things have to be kept secret for very good reasons, but when you are talking about the British Government becoming involved in covert operations and drone strikes across the world, then that is something we should have a right to know about,” he said.

“We are supposed to live in a democracy and if our Government is somehow complicit in covert actions in doing drone strikes, then I think the British people have a right to know about it.”

US attorney Jennifer Gibson, a project lead for drones with human rights organisation Reprieve, said there had been increasing evidence about the UK's involvement in US drone strikes.

“What this does is confirm with actual documentation that all that mounting evidence is absolutely true – that the UK is heavily involved in the US covert drone war in places like Yemen,” she said.

Gibson said the US drone programme had been exceptionally controversial, with accusations that it had caused the deaths of hundreds of civilians.

One report published by Reprieve in 2014 estimated attempts to kill 41 men by US drone strikes in Pakistan and Yemen had resulted in the deaths of 1,147 people.

Gibson pointed out the UK had banned the death penalty as “barbaric” - and even in countries where it is carried out there is a judicial process.

But she said in the case of drone strikes, it was intelligence agencies who decides “who lives or dies” without any accountability.

“What we found in the US covert drone programme is that despite claims from the US this is a precise weapon it turns out the intelligence behind the strikes is pretty poor and actually not that precise at all,” she said.

“Hundreds of strikes have left hundreds of civilians, if not thousands of civilians, dead without any recourse.

“The reality is that as much as the UK Government wants to say it is a matter for the states involved, they are now one of the states involved and they need to answer questions about what that involvement is, how far it has gone and what the damage has been.”

The Ministry of Defence (MoD) said US forces maintain robust “civilian and military co-operation” with the UK and manage all base activities in accordance with agreements made between the US and the UK Government.

A MoD spokesman said: “RAF Menwith Hill is part of a US Defence communications network. It wouldn’t be appropriate to comment on the specifics of a US location.”