Two thieves have stolen two paintings from the Renoir Museum in Cagnes-sur-Mer on the French Riviera after breaking into the building early on Tuesday, the town's mayor said.

The heist follows a series of high-profile art and cultural-property thefts in Europe.

What happened at the Renoir Museum?

The thieves initially took four artworks, valued together at around €9 million ($10.5 million), but abandoned two as they fled.

The thieves broke into the museum shortly before 6 a.m., Mayor Bryan Masson said.

They were detected with the help of the town's video surveillance system. Police gave chase, but the pair escaped.

Masson said that the sirens and alarms forced them to hurry and take only four paintings, two of which were ultimately "left behind in the gardens of the Renoir Museum."

The museum occupies the former home and studio of French Impressionist painter Pierre-Auguste Renoir, who spent the final years of his life in Cagnes-sur-Mer. The property is surrounded by gardens and olive trees.

What's behind recent art thefts?

The EU's law enforcement agency Europol says typically non-violent specialist gangs are increasingly being replaced by more opportunistic groups, sometimes assembled through social media.

Europol said the groups were driven by the low-risk, high-profit potential of museum heists.

High prices for precious metals, gem stones and other easily resold valuables have also made museums attractive targets.

Recent thefts have involved more brazen tactics, including the use of force or threats. The Louvre theft in Paris last year, in which €88 million worth of jewels were stolen, was cited by Europol as an example of the trend.

Editor: Elizabeth Schumacher

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