Steven Sotloff speaks before his murder by IS
Steven Sotloff speaks before his murder by ISScreenshot

Murdered journalist Steven Sotloff was kidnapped and sold to the radical Islamic State terrorist group, or ISIS, by one of the "moderate" rebel groups to whom the US government has considered offering support, according to his family's spokesman.

Barak Barfi told CNN that Sotloff - who was Jewish and a joint US-Israeli citizen - was sold for a sum of money in the tens of thousands of dollars at the Syrian border. He said credible "sources on the ground" had provided the dramatic and tragic details of the abduction.

"For the first time, we can say Steven was sold at the border," Barfi said. 

He described for the first time how Sotloff was set up to be kidnapped, as "activists" spread false rumors that he had participated in the bombing of a hospital - rumors which set him up to be kidnapped by a rebel group, and ultimately executed by IS.

"Steven's name was on a list that he had been responsible for the bombing of a hospital. This was false, activists spread his name around.

"Somebody at the border crossing made a phone call to ISIS and they set up a fake checkpoint with many people and Steven and his people that he went in with could not escape," he said.

Barfi noted that the people who actually carried out the kidnapping of Sotloff, a US citizen, were members of some of the very Syrian rebel factions the Obama administration has considered supporting to overthrow the regime of Syrian dictator Bashar al-Assad.

“We believe that these so-called moderate rebels that people want our administration to support, one of them sold him probably for something between $25,000 and $50,000 to ISIS and that was the reason he was captured,” Barfi said.

Barfi also took aim at authorities for mistreating the family, accusing them of treating Sotloff and Jim Foley - another US journalist previously executed by IS - as "pawns" in a political game. He said officials had lied to the media by claiming the families were regularly updated on the investigation, which they weren't, and that the government ignored a specific request by the family after Steven's  murder was announced.

"The relationship between the Sotloff family and the administration was very strained... we do not believe that they gave us the cooperation we need. Once Steve appeared that video the Sotloff family made one simple request of the administration and they were rebuffed on that," he claimed, but said he could not reveal precisely what the request was since it could compromise the safety of the remaining hostages.

He further accused the administration of releasing false information, for example that the hostages were constantly moved when in fact for the initial stages they were kept in the same place, as well as disturbing details of some of the torture the captives faced.

He threatened that Steven's family would go public to "set the record straight" if leaks continued to be made to the press.

"We know that the intelligence community and the White House are enmeshed in a larger game of bureaucratic infighting and Jim and Steve are pawns in this game and that's not fair and if there continues to be leaks the Sotloff family will have to speak out to set the record straight," he said.

Steven Sotloff was beheaded by the Islamic State in "revenge" for US airstrikes against the terrorists, as part of efforts to blunt its genocidal advances through Iraq.

Not long after his murder it was revealed that Sotloff was in fact Jewish and had even made aliyah to become an Israeli citizen, and that he had risked his life to observe his faith throughout his captivity. Family and friends went through extraordinary lengths to hide those facts from his kidnappers, fearing it would make his already dangerous situation far worse.

The full interview can be seen here.