Detained Palestinian lawyer Salah Hamouri has filed a complaint in France against Israeli surveillance firm NSO Group for having “illegally infiltrated” his mobile phone.

Hamouri, who holds French citizenship, was one of several activists whose phones were hacked using the Pegasus malware, according to a report in November by human rights groups.

He is currently serving a four-month term of administrative detention ordered by an Israeli military court in March on the claim he is a “threat to security”. Administrative detention allows Israel to imprison people without charge or trial for an indefinite amount of time.

The complaint, filed on Tuesday by Hamouri, the International Federation for Human Rights (FIDH) and the Human Rights League (LDH), accuses NSO of having illegally infiltrated the telephone of a rights defender.

Hamouri worked at Addameer, one of six Palestinian non-government groups Israel named a “terrorist organisation” in October.

“Obviously, this is an operation that is part of a largely political framework given the harassment Hamouri has been subjected to for years and the attacks on human rights defenders in Israel,” lawyer Patrick Baudouin, honorary president of the FIDH, told AFP.

The complaint filed to the prosecutor of the Paris judicial court could spur a judicial investigation.

Baudouin said Hamouri holds French nationality and his phone was allegedly infected with Pegasus prior to his travel to France from April to May 2021, which would make French courts “competent” to judge the case.

NSO Group has faced mounting scrutiny since a consortium of news outlets revealed that its Pegasus software had been used to spy on the phones of journalists, politicians, activists or business leaders in many countries.

Israel has refuted the accusations, saying Hamouri is a member of the Popular Front for the Liberation of Palestine, which it and the European Union consider a “terrorist” group.