The death of rebel military commander Abdel Fatah Younes has thrown a wrench into efforts to organise the makeshift opposition army and risks putting Benghazi, and perhaps the wider effort to oust Gaddafi, into disarray.
Younes was the subject of much scrutiny and scepticism among anti-regime Libyans both in the country and abroad since he became the highest-profile government figure to defect to their side, on February 20, after five days of increasingly bloody protests in Benghazi and elsewhere in the country.
Though the opposition National Transitional Council quickly made Younes chief of staff of the ragtag rebel armed forces, a power struggle ensued between Younes and longtime exile Khalifa Hifter, a former general in Muammar Gaddafi's army.
For much of March and April, control of the rebel army seemed to pass back and forth from Younes to Hifter. Sometimes it seemed neither was in control.
In recent months, the dispute seemed to resolve. The NTC presented a more disciplined public face to the media, eliminated contradictory remarks about who was in charge and minimised Hifter's role in favour of Younes.
It replaced Defence Minister Omar Hariri with Jalal al-Dogheily, a senior opposition figure who was older than both Younes and Hifter and whose job was to both coordinate military affairs and mediate between the two men.
Very little was said about Younes since then - a good sign for the NTC. But that came to an end on Thursday.
Mustafa Abdul Jalil, the chief of the NTC, blamed Younes's killing on gunmen in a press conference late on Thursday night. He said Younes had been summoned from the front line to appear for questioning before a judicial committee investigating "military affairs," but that he and two aides - a colonel and a major - were killed before he could appear.
The head of the "armed group" that killed the men was arrested, but the bodies of the men had not been found, he said.
Sources close to the NTC told Al Jazeera earlier on Thursday that Younes had been arrested and was suspected of engaging in unauthorised communication with Gaddafi's representatives and had possibly even helped supply regime troops with weapons - a dire offence against the rebel cause, but one that could not be immediately proved.
Jalil did not directly blame Gaddafi's forces for the killing, but he said the longtime leader continued to try to sow discord in the rebel ranks.
Younes's death, while possibly under investigation, throws open a power vacuum in the rebel hierarchy. Many Libyans fear such a void will spawn more violence as others move to fill his role as military commander, while his allies seek retribution.
Several theories about Younes’s death were circulating among the Libyan community and observers on Thursday night.
Gaddafi had placed a multi-million dollar bounty on Younes's head after his defection, which could have been reason alone for the assassination.
Then there was the possibility that he had been involved in a confrontation with rebel officials after being recalled from the front lines by the NTC for investigation. Some believed he had been shot after tensions flared at a meeting between the two sides, though Jalil's claim that Younes had been killed after being released from an interrogation seemed to belie that.
Finally, some believed, it was possible that Younes had been targeted for assassination by a rival, perhaps even Hifter. There was no proof to support the accusation, but it reflected a fear among Libyans in the opposition that political machinations had gotten dangerously out of control.
Younes’s home was under heavy armed guard on Thursday evening, and some Libyan activists expressed fear that his tribe, the Obeidat, would seek retribution for his killing.
Younes had been close to Muammar Gaddafi since the bloodless 1969 coup that brought the Libyan leader to power. He had attained the rank of general and served for years as Gaddafi’s trusted interior minister.
Younes also controlled a brigade of special forces troops garrisoned outside Benghazi, long known to harbour anti-Gaddafi sentiments. When he announced his defection and entered the city with his men, it swung the battle decisively in favour of the opposition and drove Gaddafi’s forces out of Benghazi, which has served as the de facto rebel capital ever since.
Yet even that pivotal victory cast a shadow. Many Benghazi residents have said that Younes, perhaps as part of a negotiation to end the fighting, allowed regime troops to escape the city. Those who escaped may have included Abdullah al-Senussi, Gaddafi’s intelligence chief, who had been dispatched to Benghazi to put down the demonstrations and was recently indicted by the International Criminal Court for organising the killing of protesters.
Younes was never enthusiastically embraced by Libyans in the east, and that made him vulnerable to a challenge.
Hifter, despite having left for exile in 1987, was warmly welcomed when he returned in March.
Hifter had led troops during Libya's war with Chad in the 1980s, after which he switched sides to join the long-simmering anti-Gaddafi movement. Hifter settled in the United States, in Virginia, five miles from the headquarters of the Central Intelligence Agency. For roughly two decades, he was involved in coordinating the Libyan opposition in exile.
Hifter’s return to east Libya was greeted happily by rebels who felt he could bring leadership to opposition forces mired in the desert west of Benghazi.
Video clips posted to opposition Facebook and YouTube pages showed Hifter touring the front lines, much as Younes had after his appointment, looking very much the general.
Hifter briefly appeared to replace Younes as the commander of the rebel forces. In late March, a spokesman for the rebel military announced as much in a press conference.
In late April, El-Siddik Hifter, the general's son, told Al Jazeera that his father was responsible for commanding rebel troops in the field, while Younes served as chief of staff back at headquarters. Omar Hariri, defence minister at the time, represented the military before the NTC, he said.
El-Siddik, who had returned to Benghazi to serve as an aide to his father, said the three men worked together as a kind of military council and made decisions collectively. Mustafa Abdul Jalil, the chairman of the NTC - and the man who sources said issued a warrant for Younes’s arrest on Thursday - was a figurehead and commander in chief only in name, Hifter said.
Despite his son's words, Hifter seemed to become marginalised. After weeks of murky struggle between Hifter and Jalil, the NTC quickly found itself backtracking.
Abdulhafiz Ghoga, the NTC's vice chairman and spokesman, told Al Jazeera in an interview a week later that Younes was at the top of the army’s chain of command.
Hariri represented the military before the NTC, it was true, but Hifter was only a commander, one of many leaders of the newly formed rebel brigades, he said.
Jalil, he said, had ultimate power as commander in chief. While day-to-day military decisions were left to commanders in the field, Jalil would have final say.
Much remains to be learned of Younes's murder. According to Jalil, he was ambushed en route to a meeting with NTC representatives. Whether they were seeking to discuss military issues or to investigate Younes’s alleged collaboration remains unclear. Also unclear is where Younes’s body has gone - Jalil said it has not been recovered.
While Jalil blamed Gaddafi loyalists for the attack, Tarik Yousef, a professor at Georgetown University who lived in Benghazi, said he discounted the idea that regime gunmen could have killed Younes, given the commander’s constant security.
"I think it's a wake-up call for the National Transitional Council to deal with the matter of security within the cities under its control," he told Al Jazeera.
The military structure, he said, is "highly undisciplined and not subject to the typical norms of command and control".
Younes's death is "a very unpleasant development at a critical moment," he said.
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