Muammar Gaddafi (Reuters photo)
Gaddafi was clearly involved in the assassination, said the official who declined to be named as the death of the general remains shrouded in mystery and investigations are underway.
The accusation, he said, was based on early reports from Tripoli that Younes had been killed, suggesting Gaddafi wanted it in a bid to get rebels to withdraw from the strategic eastern oil town of Brega.
"All these are signs Gaddafi was behind it," he told AFP.
Younes, a former interior minister in Gaddafi's government, was killed in the rebel stronghold of Benghazi after being called back from the front line which lies near Brega.
His assassination has fuelled widespread rumours amid unconfirmed reports that the rebels themselves arrested and killed him for treason.
But the opposition National Transitional Council said late Thursday that Younes was killed by an armed group after being called back from the front to answer "questions" over military matters.
The official who spoke to AFP on Friday said nobody has all the answers yet in the case but "that things will come out with time."
He downplayed the risk of any divisions in the ranks of the rebels or score-settling by tribes.
"I think this problem will pass with no big consequences because people know it is in Gaddafi's benefit and people are against Gaddafi. Even his tribes were reasonable knowing it is trap by Gaddafi to make problems."
Two of the leaders of Al-Obeidi tribe, to which Younes belongs, were alongside NTC chief Mustafa Abdel Jalil when he announced the assassination at a press conference.
Around 200 mourners paid their respects to Younes at a wake early on Friday in the premises of the assassinated general's villa in Benghazi, a witness said.
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