A jury at the trial of a student facing terror charges has been shown video of a US citizen being beheaded.
US citizen Paul Johnson pictured with his wife Noom
The High Court in Glasgow heard the footage of Paul Johnson, 49, was posted on the website of Islamic terror expert Evan Kohlmann.
He has been giving evidence at the trial of 21-year-old Mohammed Atif Siddique, from Alva, Clackmannanshire.
Mr Kohlmann denied a suggestion that the videos were worse than those Mr Siddique was said to have stored.
He said it was his intention to show the brutality of al-Qaeda.
But he denied he was playing into the group's hands by spreading propaganda.
Judge Lord Carloway warned the jury beforehand that the footage of New Jersey man Mr Johnson being beheaded would be distressing.
After it was played, Mr Kohlmann was asked what kind of research would justify publishing the clip.
He said: "This was the first video of this type al-Qaeda distributed.
"One video to show the brutality of al-Qaeda executing hostages was enough. I could not stomach any more."
Mr Kohlmann added that it also helped "identify" those involved in the beheading and that he did not list it to "advertise or cause grief".
The witness rejected accusations that he was spreading al-Qaeda propaganda.
He said: "I didn't serve any purpose for al-Qaeda."
The trial was also shown other footage taken from Mr Kohlmann's site - including a clip of distressed British hostage Ken Bigley before he was beheaded and a tank being blown up in a roadside bombing.
Mr Kohlmann denied comparisons with the material Mr Siddique was said to have stored.
Defence QC Donald Findlay said: "The material that you were asked to look at is as much the same kind found on your site.
"The difference is you put clips of people dying and people getting their heads cut off."
Mr Kohlmann replied: "No, I would not agree. I did not carry any message across. I would disagree."
Mr Siddique was arrested at his family home in Alva in April 2006.
He has been accused of possessing suspicious terrorism-related items including CDs and videos of weapons use, guerrilla tactics and bomb-making.
He has also been accused of collecting terrorist-related information, setting up websites showing how to make and use weapons and explosives, and circulating inflammatory terrorist publications.
A further charge of breach of the peace relates to claims that he showed students at Glasgow Metropolitan College images of suicide bombers and terrorist beheadings.
This charge also includes the allegation that he threatened to become a suicide bomber and claimed to be a member of al-Qaeda.
The trial, before Lord Carloway, continues.