A May 2011 file photo of General Abdel-Fattah Younis, the senior military officer leading rebel forces against Muammar Qaddafi. A former interior minister and head of Special Forces, Younis was considered a key supporter of Qaddafi before defecting

The head of the Libyan rebel’s armed forces and two of his aides were killed by gunmen Thursday, the head of the rebel leadership said.

The death of Abdel-Fattah Younis was announced at a press conference in the de facto rebel capital, Benghazi, by the head of the rebels’ National Transitional Council, Mustafa Abdul-Jalil. He told reporters that rebel security had arrested the head of the group behind the killing.

Rebel security had arrested Younis and two of his aides early Thursday from their operations room near the rebels’ eastern front.

Security officials said at the time that Younis was to be questioned about suspicions his family still had ties to Muammar Qadaffi’s regime.

Younis was Qadaffi’s interior minister before defecting to the rebels early in the uprising, which began in February.

Abdel-Jalil said that Younis had been summoned for questioning regarding “a military matter.” He said Younis and his two aides were shot before they arrived for questioning.

Abdel-Jalil called Younis “one of the heroes of the 17th of February revolution,” a name marking the date of early protests against Qadaffi’s regime.

While he criticized Qadaffi for seeking to break the unity of rebel forces, he did not say directly that Younis’ killers were associated with the regime. Instead, he issued a stiff warning about “armed groups” in rebel-held cities, saying they needed to join the fight against Qadaffi or risk being arrested by security forces.

Younis defected to the rebel side in February, but rumors have spread that he has engaged in secret talks with the Qaddafi regime.

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