Thieves have stolen about 30 paintings, including a work by Spanish master Pablo Picasso, from a private villa in the south of France, police said on Saturday.
The haul, which also included a painting by post-impressionist Henri Rousseau, was worth about 1 million euros ($1.43 million), a judicial source said.
The theft was discovered on Thursday by a caretaker at the house in the Provencal village of La Cadiere d'Azur. The owner was on holiday in Sweden at the time and has since returned to France to help the investigation, police said.
It was the second major art theft in southern France in recent days, although there was no indication the two crimes were linked.
A drawing by French impressionist Edgar Degas was stolen from a museum on Wednesday night in the Mediterranean city of Marseille. Police said the pastel work, "The Chorus," was worth an estimated 800,000 euros.