Ahmed Ramadan, one of the most influential people in Kadhafi's entourage, said Wednesday on Al-Aan television that Sadr disappeared following a meeting with the late Libyan dictator soon after arriving in Tripoli.
"I bear witness that (Sadr) came... he arrived in Libya," Ramadan said on the Dubai-based channel, adding the meeting had lasted for two and a half hours.
Two officials then "took the guests," including the cleric and those who accompanied him, and "100 percent, what we heard is that he was liquidated," said Ramadan.
Ramadan said it was "possible" that Kadhafi had given the orders for Sadr to be killed because after the meeting, "He said: 'Take him'."
He said he received the information from "some sources at the time" as well as from one of the three officials involved who had since died, and that his statements could be corroborated by "complete files."
The remains of the cleric, who would have been 83 in April, were likely to be located in either Janzur, a suburb east of Tripoli, or the southern region of Sabha, he said.
Officially invited to Libya, he arrived there on August 25, 1978, with two companions Sheikh Mohammed Yacoub and journalist Abbas Badreddin. They were seen for the last time on August 31, 1978.
His disappearance had been a source of tension between Lebanon and the Kadhafi regime, which always maintained that the cleric had left Libya for Italy.
According to an indictment against Kadhafi issued by Lebanese authorities, Kadhafi ordered Sadr to be "taken away" after the pair got into a heated argument.
Abdel Moneim al-Honi, a former colonel who took part in the 1969 coup that brought Kadhafi to power, revealed in February that Kadhafi had ordered Sadr killed during his visit and that the cleric was buried in the southern region of Sabha.
Kadhafi was killed in his hometown of Sirte on October 20 after an eight-month armed rebellion inspired by a wave of pro-democracy protests that swept the Arab world.
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