Britain's ambassador to Tehran has denied he took part in a demonstration that broke out at a memorial for the 176 people killed when a plane was shot down.

Students held a gathering at Tehran's Amir Kabir University yesterday evening to honour those killed hours after Iran admitted the Ukrainian airliner was downed by mistake.

Iran's Mehr news agency said the ambassador, Rob Macaire, was arrested for his alleged "involvement in provoking suspicious acts" at the gathering in front of the university.

"Can confirm I wasn't taking part in any demonstrations! Went to an event advertised as a vigil for victims of #PS752 tragedy," Mr Macaire said on Twitter, adding he had been detained for half an hour.

Mr Macaire thanked people for their well wishes and said it was "normal to want to pay respects" to the victims of the crash and some were British.

He said he left the vigil after five minutes when chanting started. He confirmed that he was held for about 30 minutes after he left the area.

"Arresting diplomats is of course illegal, in all countries," he said.


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The British government said Mr Macaire was arrested and detained briefly in the Iranian capital in what it called a "flagrant violation of international law".

Authorities in Tehran have yet to make any statements about the incident.

Iran's armed forces said yesterday the Ukraine International Airlines Boeing 737 was mistakenly shot down, after denying for days Western claims it was brought down by a missile.

Police dispersed students who chanted "radical" and "destructive" slogans when the tribute to those killed in the air disaster turned into an angry demonstration, Fars news agency reported.