Dar es Salaam (Reuters) - Mohammed Emwazi, the Briton identified as Islamic State killer "Jihadi John", was denied entry to Tanzania in 2009 at the request of British security services, a Tanzanian police source said on Tuesday.
The source's version of events tallies with emails published by London activist group Cage last week that they said were from Emwazi, recently named as the militant shown beheading American, British and Syrian hostages on IS videos.
Security officers at Dar es Salaam airport refused to allow entry to Emwazi and two friends - another Briton and a German - because they were on an official immigration stop list, said the source who spoke to Reuters on condition of anonymity.
Immigration officials said the request came from British intelligence rather than the international police organization Interpol, the source added. British security officials would not comment on the episode.
"When Emwazi and his friends were told they would not be allowed to enter Tanzania, they caused a commotion and tried to force their way out of the airport," the source said.
"I think the stop order against Emwazi and his friends was issued at the request of the British intelligence service."
In meetings and email exchanges with Cage between 2009 and 2012, Emwazi said he and two friends had gone to Tanzania in August 2009 for a safari holiday after he completed his studies in computer programming at London's University of Westminster.
He told Cage he was deported from Tanzania to Britain via Amsterdam, and quizzed by agents from Britain's MI5 domestic security service who told him they believed he was attempting to reach Somalia to join the Islamist militant group al Shabaab, something he denied.
Court documents from 2011 have also shown that Britain suspected him of being part of a network involved in procuring funds and equipment "for terrorism-related purposes" in Somalia.
Senior Tanzanian law enforcement officials, including the acting director of criminal investigation (DCI), Diwani Athumani, have declined to comment on the events of 2009.
The Tanzanian source said Emwazi and his friends were arrested for disturbing the peace at the airport and detained for several hours at the Stakishari Ukonga police station.
They were then picked up by local immigration officials and taken for further questioning before being deported on a KLM flight, the source added.
Since his unmasking as "Jihadi John", there has been much media speculation about when and where Emwazi was radicalized.
The British court documents show British officials believe he was an associate of Bilal al Berjawi, a leader of the Somali-based militant group al Shabaab who was killed in a U.S. drone strike in 2012.
But Cage, which has released what it said was an audio recording of Emwazi made after he returned to Britain in 2009, has said Emwazi complained to them about being harassed by Britain's MI5 who he said had tried to recruit him.
The police source told Reuters that Emwazi was not mistreated by Tanzanian officials in Dar es Salaam.
"Emwazi was never tortured in Tanzania," the source said. "In fact, (he and his friends) caused a fracas at the airport after being told they were prohibited from entering the country due to the presence of an immigration stop order against their entry."
Emwazi also told Cage that from July 2010 onwards he was repeatedly prevented by the British authorities from returning to his birthplace Kuwait where he had a job and was planning to get married.
Cage's Research Director Asim Qureshi has argued this might have played a part in turning him into the man who appeared clad in black and brandishing a knife in the IS videos.
Writing by Michael Holden; Editing by Sophie Walker