A Stanford Professor has used United Nation security officers to silence a journalist asking him "inconvenient questions" during a press briefing at the climate change conference in Copenhagen.
Professor Stephen Schneider's assistant requested armed UN security officers who held film maker Phelim McAleer, ordered him to stop filming and prevented further questioning after the press conference where the Stanford academic was launching a book.
McAleer, a veteran journalist and film maker, has recently made a documentary "Not Evil Just Wrong' which takes a sceptical look at the science and politics behind Global Warming concerns.
He asked Professor Schneider about his opinions on Climategate - where leaked emails have revealed that a senior British professor deleted data and encouraged colleagues to do likewise if it contradicted their belief in Global Warming.
Professor Phil Jones, the head of Britain's Climate Research Unit, has temporarily stood down pending an investigation into the scandal.
Professor Schneider, who is a senior member of the UN's Intergovernmental Panel on Climate Change (IPCC), said he would not comment on emails that may have been incomplete or edited.
During some testy exchanges with McAleer, UN officials and Professor Schneider's assistants twice tried to cut short McAleer's question.
However as the press conference drew to a close Professor Schneider's assistant called armed UN security guards to the room. They held McAleer and aggressively ordered cameraman Ian Foster to stop filming. The guard threatened to take away the camera and expel the film crew from the conference if they did not obey his instructions to stop filming Professor Schneider.
The guard demanded to look at the film crews press credentials and refused to allow them to film until Professor Schneider left the room.
McAleer said he was disappointed by Professor Schneider's behaviour.
"It was a press conference. Climategate is a major story - it goes to the heart of the Global Warming debate by calling into question the scientific data and the integrity of many scientists involved."
"These questions should be answered. The attempts by UN officials and Professor Schneider's assistant to remove my microphone were hamfisted but events took a more sinister turn when they called an armed UN security officer to silence a journalist."
Two officers corralled the film crew and one officer can be seen on tape threatening the cameraman. The Guard can also be heard warning that if the crew did not stop filming their would seize the equipment and the journalists expelled from the conference.
McAleer says he has made an official complaint about the incident.
"I have met Mr Christopher Ankerson the UN's head of security for the conference and he has confirmed it was Professor Schneider's staff who asked the security guards to come corral us at the press conference. Mr Ankerson could not say what grounds the security guard had for ordering us to stop filming."
"This is a blatant attempt to stop journalists doing journalism and asking hard questions. It is not the job of armed UN security officers to stop legitimate journalists asking legitimate questions of senior members of the UN's IPCC."
Professor Schneider was interviewed for McAleer's "Not Evil Just Wrong" documentary but lawyers later wrote to McAleer saying he was withdrawing permission for the interview to be used.
McAleer, who is from Ireland, has gained quite a reputation for asking difficult questions of those who have been promoting the idea of man-made Global Warming.
His microphone was cut off after he asked former vice-president Al Gore about the British court case which found that An Inconvenient Truth had a nine significant errors and exaggerations. Almost 500,000 people have watched the incident on youtube.