US journalists and lawyers who visited WikiLeaks founder Julian Assange have filed legal action against the CIA and its former director, Michael Pompeo.

They also filed a lawsuit against Spanish security firm Undercover Global and its former chief executive David R Morales Guillen, claiming they violated constitutional rights.

Assange is being held in London’s Belmarsh prison as he fights extradition to the US.

Julian Assange extradition
Julian Assange appearing by video link at the High Court in London last year (Elizabeth Cook/PA)

He has been imprisoned since he was dragged out of the Ecuadorian embassy in London in 2019.

More than 40 human rights organisations including Amnesty International have called for Assange’s release.

The lawsuit was filed in the Southern District of New York and alleges that Mr Pompeo oversaw and directed a campaign of illegal spying on Assange’s lawyers and others inside the Ecuadorian embassy.

Richard A Roth, lead counsel for the plaintiffs, said: “The United States Constitution shields American citizens from US government overreach even when the activities take place in a foreign embassy in a foreign country.

Michael Pompeo
Michael Pompeo (John Raoux/AP)

“Visitors who are lawyers, journalists and doctors frequently carry confidential information in their devices.

“They had a reasonable expectation that the security guards at the Ecuadorian embassy in London would not be US government spies charged with delivering copies of their electronics to the CIA.”

Assange’s wife, Stella Moris Assange, said: “Julian’s young boys miss their father. Not in my worst nightmares could I have ever envisioned the ferocity of attacks against Julian and the entitled arrogance and ‘above the law’ actions that are being carried out against my husband.”