The "Jungle" migrant camp near the French port of Calais woke up Wednesday to a third day of clearance work following a night of shelter-burning and some gas-bottle explosions.
A Calais prefecture official told France Info radio on Wednesday morning that one person had been slightly injured in his inner ear by one of the explosions and had been taken to hospital.
"The operation will continue today to remove the empty shelters and to avoid them being set fire to again," a prefecture spokesman told Reuters.
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Late on Tuesday, regional prefect Fabienne Buccio said it was difficult to prevent the fires.
"Some migrants follow traditions - we asked them not to do it — but they set ablaze their tents and their shelters when they leave," she said.
"We told them not to do it, but some...do it anyway. We are on standby, the fire brigade is in the vicinity to guarantee security and to prevent the fire from spreading. It's part of a tradition. Even if we would like them to refrain from doing it, they do it."
Migrants fleeing poverty and war outside Europe have over the past few years congregated at Calais, the main port entry to Britain from France, in the hope of finding new lives across the short stretch of sea.