The massive blaze that swept through Notre Dame cathedral was an “accident” — and is now fully extinguished, French officials said Tuesday.

A team of 50 investigators is now working to pinpoint the cause of the fire, which destroyed parts of the iconic 12th-century structure the day before.

“This was an accident,” said Valérie Pécresse, the president of the Île-de-France region which covers Paris, CNN reported. “It wasn’t intentional.” 

Paris prosecutor Remy Heitz said there is no evidence of arson and that investigators are working under the assumption that the inferno was an accident.

He said the probe will be “long and complex” and will involve interviews with workers from five companies that had been hired as part of a $12 million renovation of the 850-year-old cathedral.

Meanwhile, a spokesman for the Paris firefighters confirmed Tuesday morning that “the entire fire is out.”

“This phase is for the experts,” said Gabriel Plus.

The fire burned for several hours after breaking out early Monday evening on the roof, which was constructed from giant oak beams, including some dating back to the 13th century.