Rebel forces chief commander Abdel Fattah Younes speaks during a rally in the rebel-held city of Benghazi, Libya earlier this month. (Photo: AP Photo/Sergey Ponomarev)

BENGHAZI, Libya (AP) — A rebel special forces member accused fellow Libyan rebels on Friday of killing the movement's military chief, pointing to a potentially major split in the ranks of the opposition battling Moammar Gadhafi.

An angry Mohammed Agoury told The Associated Press that he was present when a group of rebels from a faction known as the February 17 Martyrs' Brigade came to Abdel-Fattah Younis' operations room outside Benghazi before dawn on Wednesday and took him away with them for interrogation.

Agoury said he tried to accompany his commander, "but Younis trusted them and went alone."

"Instead, they betrayed us and killed him," he said.

The February 17 Martyrs Brigade is a group made up of hundreds of civilians who took up arms to join the rebellion. Their fighters participate in the front-line battles with Gadhafi's forces, but also act as a semi-official internal security force for the opposition. Some of its leadership comes from the Libyan Islamic Fighting Group, an Islamic militant group that waged a campaign of violence against Gadhafi's regime in the 1990s.

Agoury said the brigade had an agenda against Younis, because he was previously Gadhafi's interior minister and was involved in the crackdown that crushed the LIFG.

Younis defected to the rebellion early in the uprising that began in February, bringing his forces into the opposition ranks — a move that at the time raised Western hopes that the uprising could succeed in forcing out the country's ruler of more than four decades. But some on the rebel side remained deeply suspicious of him because of his longtime ties to Gadhafi.

"They don't trust anyone who was with Gadhafi's regime, they wanted revenge," said Agoury.

A member of the Martyr's Brigade said his group had evidence that Younis was a "traitor." He told the AP that "the evidence will come out in a few days." The brigade member spoke on condition of anonymity because he feared reprisals.

Younis' body, along with those of two colonels who were his top aides, were found on Thursday, dumped outside Benghazi, the rebels' de facto capital. Their bodies had been burned.

The head of the rebel National Transitional Council, Mustafa Abdul-Jalil, blamed "gunmen" and said one man had been arrested, but Abdul-Jalil did not say what he believed motivated the killers.

Abdul-Jalil said Younis had been "summoned" to Benghazi for questioning on a "military matter" and was killed along with two aides while on route.

But hours before the commander's death was announced, rebel military spokesman Mohammed al-Rijali had said Younis was taken to Benghazi for "interrogation" on suspicion his family might still have ties to Gadhafi regime, raising questions about whether he might have been assassinated by his own side.

The city of Benghazi woke up to fierce shooting Friday morning, as the news of Younis' death spread confusion and suspicion in the city.

Thousands marched in Younis' funeral procession on Friday, as men draped the rebel tricolor flag over his coffin and carried it to a cemetery, where he was buried.

Younis' son, Ashraf, broke down, crying and screaming as they lowered the body into the ground.

"We want Moammar to come back! We want the green flag back!" he shouted at the crowd, betraying his frustration with the months of chaos in the country and a desire for a return to normalcy.

At the funeral, Younis' nephew Mohammad al-Obaidi called Younis a martyr and a champion of the Libyan uprising, while the crowd broke into chants of "The martyr is God's beloved" and "Allah is Great."

At the cemetery, Younis was given a military farewell with a 300-soldier salute beore being buried. The crackling of machine guns shot in the air competed with the crowds chanting.

Younis' deputy Col. Suleiman Mahmoud has taken over the military's duties in Benghazi.