An operation to clear 'the jungle' is underway.

Against a backdrop of burning huts, workers guarded by scores of French police began tearing down the sprawling migrant camp known as "the jungle" on the outskirts of Calais on Monday.

Calais Jungle refugee camp removed Feb 29 2016 French police

(Carl Court/Getty)

Police used tear gas and water cannons to clear the hold-outs.

Calais Jungle refugee camp removed Feb 29 2016 89524845 tear gas

(Carl Court/Getty)

Calais Jungle refugee camp removed Feb 29 2016 89525224 activists sprayed

(Carl Court/Getty)

Reporters captured it on video.

The clash started when people threw stones and bits of rubble.

French police quickly formed a security cordon and the skirmish ended with three arrests, authorities said. There were no reports of injuries.

Calais Jungle refugee camp cleared Feb 29 2016 arrests

(Pascal Rossignol/Reuter)

With tensions running high, crews moved in.

Helmeted workers began to rip down the makeshift shelters that have housed some 4,000 people dreaming of a new life in western Europe.

Calais Jungle refugee camp cleared Feb 29 2016 89521701 workers protected

(Carl Court/Getty)

Calais is less than 35 kilometres from Dover, across the Channel.

A flash point on the French side of the English Channel, Calais's massive refugee camp sprang up less than a year ago near a ferry terminal and the Eurotunnel rail route to Britain.

Several efforts to clear the camp have been carried out in the past, but the dismantling of its dense southern portion, where the present operation is underway, is the most aggressive operation to date.

Calais Jungle refugee camp removed Feb 29 2016 89525064 water cannons

(Carl Court/Getty)

Thousands of refugees are affected by the evictions.

Humanitarian groups contend more than 3,000 people are affected. French authorities are relocating those displaced to purpose-built accommodation nearby or to centres around France where they can decide whether to apply for asylum.

Many have resisted the move, fearing it will hurt their chances of reaching Britain, and migrant advocates say there isn't enough space in the new areas.

Calais Jungle refugee camp removed Feb 29 2016 89524804 flaming huts

(Carl Court/Getty)

With files from The Associated Press