Al Fayed was accused by more than 20 women of sexual assault in a BBC documentary and podcast in September 2024.
Several suspects were taken into police custody. Those measures were lifted after their interviews, specifically so investigators could analyze digital material seized during the searches.
It is the first time any arrests have been made in relation to alleged abuse and trafficking by the former owner of Harrods and the Ritz.
Met officers took part in what is understood to be a joint operation between British and French authorities.
"We believe that all properties owned by Fayed should be investigated with the same thoroughness as those already searched, wherever they are located, to ensure that no potentially relevant evidence is overlooked,"the group said. The survivor advocacy group No One Above said France was treating the case as organised human trafficking, led by specialists, with properties searched and evidence seized.
"We hope these developments represent meaningful progress towards identifying and holding to account all those who facilitated, concealed or assisted his offending, wherever they operated,"the group said. French police have arrested several suspects in an investigation into alleged sexual abuse and trafficking linked to Mohamed Al Fayed, police said.