Investigative website Disclose published a series of articles in November 2021 based on hundreds of secret documents.

It said they showed how information from a French counter-intelligence operation in Egypt, codenamed “Sirli”, was used by the Egyptian state for “a campaign of arbitrary killings” against smugglers operating along the Libyan border.

On Tuesday, Lavrilleux’s home was searched and she was arrested for questioning by agents of the DGSI, France’s domestic intelligence agency, Disclose announced on X, formerly known as Twitter.

It denounced an “unacceptable attack on the secrecy of sources” – a view quickly backed by the Society of Journalists and Reporters Without Borders (RSF).

“We fear that the DGSI’s actions will undermine the secrecy of the sources,” RSF said.

Amnesty International’s secretary-general Agnes Callamard said, “It is deeply chilling that, almost two years after the revelations that France was allegedly complicit in the extrajudicial executions of hundreds of people in Egypt, it is the journalist who exposed these atrocities that is being targeted, rather than those responsible.”