Children were among those affected by tear gas fired by police as the authorities moved in to demolish part of the 'Jungle' camp in Calais.

A British MP who witnessed the evictions described the scene as "carnage" and lambasted the "inhumane treatment" of the migrant inhabitants.

Trouble flared as demolition teams started tearing down the shanty dwellings in the southern part of the notorious slum, which is home to around 4,000 people, many of whom want to reach the UK.

Riot police fired tear gas reportedly in response to protesters hurling stones. 

Officers also used water hoses to disperse migrants, while fires broke out in some of the shacks.

The demolition work got under way after a legal ruling cleared the way for the mass evictions from the most populated half of the site.

Speaking to Sky News, Conservative MP David Burrowes was deeply critical of the "inhumane treatment" suffered by the migrants.

He said: "It is carnage. It's is not the way to treat any human being, particularly those who have come from a country probably where they have faced trauma, they have faced forcible eviction and they have faced violence.

"There was a promise of trying to deal with them in a considered, voluntary way, and to ensure that people were treated humanely. This is not the way to do it."

The authorities plan to relocate people to a nearby container park and reception centres across France.

However, campaigners had called for the evictions to be delayed, arguing there was not enough alternative accommodation.

Aid agencies have said the action will affect around 3,500 people, although state officials put the figure much lower at up to 1,000.

Repeated attempts by migrants from the camp to get through the Channel Tunnel or stow away on lorries to reach Britain have caused continuing disruption on the vital transport link.

The site has also been a source of tension with the local French population and forced the police to maintain a large presence in the area.