The investigation into the theft of two Renoir paintings from a small museum on the French Riviera has taken a dramatic turn. Police in Marseille say the suspects were in the final stages of planning a second museum burglary, this time targeting the Fondation Maeght in Saint-Paul-de-Vence, one of Europe's great collections of modern art. Prosecutor Nicolas Bessone told reporters on Monday that the arrests of six people on October 7 were brought forward because investigators had a very strong suspicion another heist was imminent. Surveillance showed the main suspect, a 29-year-old man, visiting the Maeght foundation on October 3 and then meeting a fourth man with earlier art-theft and forgery convictions. The suspects deny the allegations. The Renoir theft itself happened on September 8, when intruders cut through a fence at the Renoir Museum in Cagnes-sur-Mer. They escaped with Portrait of Madame Colonna Romano and Young Woman at the Well, abandoning two other paintings as they fled. DNA on a protective covering left in the garden identified the 29-year-old, whose vehicle was already under surveillance in a separate drug-trafficking inquiry. The two paintings, valued at about 4.2 million euros and on loan from the Musée d'Orsay, were recovered behind a concrete-block and plasterboard wall in a house in Clermont-l'Hérault. Both were damaged, one with a torn canvas, and have been sent to a restoration centre in Marseille. The mayor of Cagnes-sur-Mer called their recovery a tremendous relief for the town. Of the six people arrested, four men were charged; two were remanded in pre-trial detention while maintaining their innocence, and two others were released under judicial supervision with travel restrictions. The investigation also revealed the thieves had used an electric saw to cut through the museum's fence and had abandoned two further Renoirs in the garden as they fled, a sign of how close the September theft came to being far worse.