The sister of kidnapped Scottish journalist Alan Johnston was among 6000 walkers taking in some of Edinburgh's favourite landmarks in the Great Scottish Walk yesterday.

Katriona Johnston, wearing a T-shirt displaying a picture of her brother and the slogan Free Alan Johnston, took part in the walk to raise awareness about the plight of the BBC correspondent who was abducted in the Middle East nearly three months ago.

On the eve of her walk, Palestinian Information Minister Mustafa Barghouti called for the release of Mr Johnston when speaking at a rally on Saturday attended by thousands of demonstrators in London to mark the 40th anniversary of the occupation of the West Bank, Gaza and East Jerusalem.

Palestinian forces are said to be considering a raid to free him from his captors, the self-proclaimed Army of Islam, in the Gaza Strip.

Ms Johnston and the rest of the Johnston family were said to be "buoyed up" after seeing the first video of the BBC reporter since he was snatched off the street in Gaza City on March 12. It was recently broadcast on a militant website.

Mr Johnston, 45, whose parents live in Argyll, was pictured from the waist up wearing a red sweatshirt as he delivered a statement lasting around five minutes to the camera.

He was about to outline conditions for his release, when the tape cut away to an unidentified voice in Arabic demanding freedom for Islamic prisoners, including a radical cleric, with ties to al Qaeda, imprisoned in Britain.

The walk, which has raised hundreds of thousands of pounds for charity, was led yesterday by Lord Provost George Grubb and the George Watson Pipe Band. It has raised more than £6m in its 10 years.

After setting off from Meadowbank Stadium, the walkers carried out one, six or twelve mile walks.

The route included the Grassmarket, Princes Street Gardens and Ocean Terminal.

A walk spokesman said: "The event has been gradually getting bigger and bigger. This year it was good to see so many more people in fancy dress. It was a great day."