Tom MacMaster's wife has confirmed in an email to the Guardian that he is the real identity behind the Gay Girl in Damascus blog

The mysterious identity of a young Arab lesbian blogger who was apparently kidnapped last week in Syria has been revealed conclusively to be a hoax. The blogs were written not by a gay girl in Damascus, but a middle-aged American man based in Scotland.

Tom MacMaster, a 40-year-old Middle East activist studying for a masters at Edinburgh University, posted an update declaring that, rather than a 35-year-old feminist and lesbian called Amina Abdallah Araf al Omari, he was "the sole author of all posts on this blog".

"I never expected this level of attention," he wrote in a posting allegedly emanating from "Istanbul, Turkey".

"The events [in the Middle East] are being shaped by the people living them on a daily basis. I have only tried to illuminate them for a western audience."

The admission – confirmed in an email to the Guardian from MacMaster's wife – apparently ends a mystery that has convulsed parts of the internet for almost a week. But it provoked a furious response from those who had supported the blogger's campaign, with some in the Syrian gay community saying he had risked their safety and seriously harmed their cause.

The blog A Gay Girl in Damascus was launched in February, purportedly to explain "what it's like to be a lesbian here", and gathered a growing following as Syria's popular uprising gained momentum in recent months. Amina described participating in street protests, carrying out furtive lesbian romances and eventually being forced into hiding after security forces came to her home to arrest her.

Then, on 6 June, a post appeared in the name of Amina's cousin "Rania O Ismail", who said the blogger had been snatched by armed men on a Damascus street. The news sparked internet campaigns to release her, until activists in Syria and beyond began voicing doubts.

It emerged that no one, even a woman in Canada who believed she was having a relationship with Amina, had ever spoken to her, and other key details could not be corroborated.

In recent days an army of bloggers, journalists and others uncovered snippets of evidence that pointed increasingly to MacMaster and his wife, Britta Froelicher, who is studying at the University of St Andrews for a PhD in Syrian economic development.

IP addresses of emails sent by Amina to the lesbian blog LezGetReal.com and others were traced to servers at Edinburgh University. A now-defunct Yahoo discussion group supposedly jointly run by "Amina Arraf" was listed under an address in Stone Mountain, Georgia, that public records show is a home owned by MacMaster and Froelicher.

Many private emails sent by the blog's author contained photographs identical to pictures taken by Froelicher and posted on her page on the Picasa photo-sharing website. Included on the site are many images from a trip to Syria in 2008. The pictures had been removed from public view by Sunday night.

With the evidence increasingly compelling, MacMaster, who apparently moved to Edinburgh with his wife late last year, decided to come clean. "While the narrative voice may have been fictional, the facts on this blog are true and not misleading as to the situation on the ground," the update read. "This experience has, sadly, only confirmed my feelings regarding the often superficial coverage of the Middle East and the pervasiveness of new forms of liberal Orientalism. However, I have been deeply touched by the reactions of readers."

Despite MacMaster's assertion "I do not believe that I have harmed anyone", activists were furious. Sami Hamwi, the pseudonym for the Damascus editor of GayMiddleEast.com, wrote: "To Mr MacMaster, I say shame on you!!! There are bloggers in Syria who are trying as hard as they can to report news and stories from the country. We have to deal with too many difficulties than you can imagine. What you have done has harmed many, put us all in danger, and made us worry about our LGBT activism. Add to that, that it might have caused doubts about the authenticity of our blogs, stories, and us.

"Your apology is not accepted, since I have myself started to investigate Amina's arrest. I could have put myself in a grave danger inquiring about a fictitious figure. Really … Shame on you!!!"

"What a waste of time when we are trying so hard to get news out of Syria," another Damascus activist told the Guardian.

Twitter supporters and bloggers also reacted furiously. There was no immediate reaction from Sandra Bagaria, the French Canadian woman who exchanged around 1,000 emails with Amina and believed herself to be in a romantic relationship with her. Jelena Lecic, the London woman whose pictures were appropriated by the blogger and passed off as Amina, including in direct email correspondence with the Guardian, was not immediately available for comment.

Katherine Marsh, the pseudonym of a journalist who until recently was reporting for the Guardian from Syria, interviewed Amina by email in May after being put in touch with her by a trusted Syrian contact who also believed the blogger to be real.

Marsh said that many steps had been taken to try to verify Amina's identity, including repeated requests to meet, at some personal risk to the journalist, and to talk on Skype.

Amina agreed to meet but later emailed to say she had seen security forces and had therefore not come to the meeting. She then emailed details of her supposed hiding place, lending credence to her story.

Despite the explanations offered in the blogpost, the question many were asking last night was why. In response to an email from the Guardian, Froelicher said she and her husband "would be giving the first interview to a journalist of [their] choice in 12-24 hours". In a message to another journalist, she said: "We are on vacation in Turkey and just really want to have a nice time and not deal with all this craziness at the moment."

• The photograph on this article was changed on Monday 13 June because a positively verified picture of Tom MacMaster was not available.