A foul-smelling cloud of gas escaped from a factory in northern France on Tuesday, making life unpleasant from the outskirts of Paris to Britain's shores and prompting scores of emergency calls.

France's Interior Ministry released a statement saying the mercaptan gas escaping from the Rouen chemical factory is harmless. Among other uses, mercaptan is added to otherwise odorless municipal gas to alert people of leaks. The factory has been shut down, and environmental authorities are carrying out tests.

While authorities reassured residents no to worry, winds carried the smell across hundreds of square miles.

Police in the coastal English town of Hastings reassured residents in a tweet with the hashtag "noneedtopanic" that mercaptan from Rouen was the likely cause of the odor.

The London Fire Brigade tweeted that it had received five times as many calls about potential gas leaks before 10:30 Tuesday morning than it had taken all of the day before. The response? Hashtag "mondieu."

The factory in the northern city of Rouen is owned by Lubrizol, a subsidiary of investor Warren Buffett's Berkshire Hathaway.

"Bearing in mind the lack of danger, residents of the areas concerned are asked not to call emergency services," the Interior Ministry said.

Charly Triballeau / AFP - Getty Images

A gas leak at this chemical plant in the Normandy city of Rouen could be smelled as far away as Paris and London. Officials say it is harmless.

The local government posted a message on its website, asking people not to call emergency services and instead set up a hotline to answer questions about the smell.

Pierre-Jean Payrouse, the director of internal operations for the factory, said he hoped the leak would be stopped by Tuesday evening.

But not in time for a French Cup soccer game scheduled for the evening; authorities postponed the Marseille-Rouen match.