The ordeal began the day after the team arrived in Tripoli to film a documentary on Lebanese imam Musa al-Sadr, who was invited to Libya in 1978 then vanished.
The trio, who have not been named, along with news reporter Kassem Hamadé, were bundled into a car then thrown into tiny cells at a Libyan prison.
They spent the next five days being interrogated by Libyan intelligence authorities and, according to Kassem, told by a guard they would be killed.
All four were finally released after diplomatic pressure from the the UK foreign office, the Swedish government and the BBC, the Daily Mail reports.
The BBC said the team had full permission to be in the country and gather material for the documentary.
Kassem wrote about the frightening experience for Swedish newspaper Expressen.
He said he didn’t know why the crew were detained but suspected the documentary had spooked people in the Libyan intelligence community who were formerly loyal to Libyan dictator Muammar Gaddafi.
The reporter recalled the horror of being told by a prison guard: ‘You will die. We will cut you to pieces and bury you here. No one knows you’re here, it goes blank.’
He added: ‘The last word – blanco – I know all too well what it means. I have met people who were tortured ‘in blanco’. They have been suspended by their wrists with the help of a winch until only the tips of their toes touch the ground.
‘In that position, they have since been subjected to mindless violence. Those I have met were lucky to make it out alive. Many do not. How will it go for us?’
Kassem said he and the BBC team, made up of a reporter, a cameraman and a producer, had arrived in Tripoli to make the documentary about Musa al-Sadr.
At the airport, security staff eyed the team with suspicion and kept them waiting three hours before allowing them through passport control, he explained.
Two local drivers and a body guard were waiting for them in the airport carpark and, according to Kassem, ‘acting like we were in a war zone’.
He said they’d been booked into a hotel before arriving, but once in the city officials rebooked them into the city’s Radisson, telling them it was cheaper.
The next day the crew were awaiting further accreditation at the Foreign Ministry’s headquarters near the hotel when a number of officials arrived and forced them into a waiting car.
He said he was in a state of shock and whispered to the others: ‘We are kidnapped.’
The person who appeared to be in command asked if they knew who he was and added if they didn’t they would soon find out.
Kassem whispered again to the others, this time saying he hoped it wasn’t ISIS or al-Qaeda.
While interrogated at the prison Kassem said he was accused of being a spy for Lebanon, then told he’d visited Israel before, which, he said, he hasn’t.
Later, when he said he worked for the Swedish newspaper Expressen, they allegedly told him it was not a newspaper but a government information agency and that he was passing on intelligence to Sweden, before claiming he was in Libya to assassinate someone.
Even when the crew was finally released and driven to the airport, Kassem feared they might be killed on the way.
But, he said, all four arrived safely at the airport and were relieved to fly home.
A BBC spokesperson told Metro.co.uk: ‘A small team working for the BBC entered Libya in March of this year with full permission, to gather material for a story. They were subsequently detained and interrogated over a number of days by the Libyan intelligence authorities.
‘The interrogation took place despite our authorised access to the country and without clear motive. We stand by our journalists and are deeply concerned about the treatment of this team. The safety of those working for the BBC is our first priority and we continue to support this team.’
A Foreign Commonwealth and Development Office spokesperson said they supported four British men who were released from detention in Libya and raised their cases directly with the Libyan authorities.
The subject of the planned documentary, Musa al-Sadr, was a prominent Shia Muslim leader for two decades before he vanished. It’s said he helped to transform Lebanon’s Shia from a once-ostracised community to a politically powerful group.
Libya has always denied any involvement in his disappearance. It’s widely believed he was kidnapped and executed.
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