THE HAGUE, Netherlands (AP) — Romanian authorities have arrested three suspects in last year’s multimillion-dollar art heist from a Netherlands art gallery, Dutch police said Tuesday. But the paintings, by artists including Picasso, Matisse and Monet, have not been recovered.

The announcement marked the first breakthrough for police since thieves broke open an emergency exit and swiped the seven pieces on Oct. 16 in a late night raid at the Kunsthal gallery in Rotterdam.

It was the biggest art theft in more than a decade in the Netherlands. The stolen works have an estimated value of tens of millions of dollars if they were sold at auction, but art experts said that would be impossible following the theft.