Romanian police on Friday said they had made another arrest linked to the spectacular 2012 art heist at Rotterdam's Kunsthal museum, detaining the mother of one of the male suspects.
Judicial sources said Olga Dogaru, whose son Radu Dogaru was arrested in January for direct involvement in the robbery, was arrested on suspicion of complicity in the theft of seven paintings by Picasso, Gauguin, Matisse and Monet.
Experts have estimated the paintings' value at more than 100 million euros ($130 million).
The heist gripped the Netherlands and the art world as police apparently struggled to piece the crime together, despite putting 25 officers on the case.
Six Romanians have so far been charged in connection with the heist.
The works stolen include Picasso's "Tete d'Arlequin", Monet's "Waterloo Bridge" and Lucian Freud's "Woman with Eyes Closed".
It is not clear what has happened to the paintings even though a suitcase allegedly used to store them has been found in Romania.