CALAIS, France -- About two dozen people protesting the demolition of a sprawling migrant camp in northern France climbed onto shanty rooftops on Tuesday, briefly stalling the tear-down.

Bulldozer crews plowed through blustery, damp winds, working around the protesters, who ultimately came down from the buildings. By mid-afternoon, the demolition was proceeding unimpeded.

Earlier in the day, a man and a woman standing together on a rooftop had warned police not to approach. The woman then cut her wrists as officers moved forward. Baton-wielding police beat the man and both were removed from the roof. The woman was conscious, but her condition wasn't immediately known.

The slow removal of the encampment in Calais has angered migrants who live there in squalid conditions in hopes of reaching a better life in Britain.

France's government has offered to relocate uprooted migrants into heated containers or to centres around France where they can decide whether to apply for asylum, and officials have blamed activists from the group No Borders for the ongoing unrest. But many migrants resist French offers of help, afraid of hurting their chances to reach Britain.

The city bordering the Channel has ferry links and the Eurotunnel rail to England, and is temporary home to an estimated 4,000 migrants, down from 6,000 in December. The camp has become a flashpoint between France and Britain, fueling far-right support in both countries.

"This operation will continue in coming days, calmly and methodically, providing a place for everyone as the government has committed," French Interior Minister Bernard Cazeneuve said in a statement Tuesday.