The veteran peace campaigner Brian Haw, who became a fixture in Parliament Square over the past decade, has died after "a long hard fight" against lung cancer, his family has announced.

The 62-year-old died in his sleep on Saturday in Germany, where he had been receiving treatment.

Haw began his round-the-clock protest opposite the Houses of Parliament on 2 June 2001.

The camp was initially a response to economic sanctions and British and US bombing raids on Iraq, but it grew in scope after the 9/11 attacks on New York and Washington DC, and the invasions of Afghanistan and Iraq that followed.

His tent, his collection of pictures of war victims and his handwritten posters were a familiar sight in the square and successive attempts to remove him failed after the high court said it would be a breach of his human rights.

In a statement on Haw's website, his family said: "It is with deepest regret that I inform you that our father, Brian, passed away this morning. As you know he was battling lung cancer, and was having treatment in Germany. He left us in his sleep and in no pain, after a long, hard fight."

Earlier this year the Greater London Authority evicted Haw and his supporters from the square's grass area, forcing them on to the footpath.

Westminster council plans to go to court to try to get the camp moved off the footpath, which could see it disappear permanently.

Fellow members of his peace campaign said on his website that the authorities "should forever be ashamed of their disgraceful behaviour towards Brian", adding: "Brian showed great determination and courage during the many long hard years he led his peace campaign in Parliament Square, during which it is well documented that he was relentlessly persecuted by the authorities, which eventually took its toll on his health.

"Brian showed the same courage and determination in his battle with cancer. He was keenly aware of and deeply concerned that so many civilians in Iraq, Afghanistan and Palestine did not have access to the same treatments that were made available to him. Parliament, the police, and courts should forever be ashamed of their disgraceful behaviour towards Brian."

Over the past 10 years civil rights campaigners have supported Haw as he saw off various attempts to force him to move.

In November 2004, ministers announced provisions in the Serious Organised Crime and Police bill that could have seen him removed from the square.

The legislation, passed in April 2005, restricted the right to protest in designated areas within 1km (about half-a-mile) of parliament.

Initially, the high court ruled Haw's protest was not covered by the act because it started before the new law came into effect.

But the case was taken to the appeal court which, in May 2006, ruled he would have to apply to the police under the act for permission to continue his demonstration."