Talks between Sudan's ruling generals and protest leaders, held after weeks of standoff following a deadly crackdown on protesters, enter a second day Thursday with the key issue of forming a new governing body still unresolved.
Sudan has been rocked by a political crisis since the army ousted longtime ruler Omar al-Bashir in April on the back of widespread protests, with the ruling generals resisting demonstrators' demands to hand power to a civilian administration.
The generals had previously agreed over a broad civilian structure, but talks between the two sides collapsed in May following a disagreement over who should lead an overall new governing body -- a civilian or a soldier.
Tensions further surged between the generals and protest leaders after a deadly pre-dawn raid on a longstanding protest camp in Khartoum on June 3 killed dozens of demonstrators and wounded hundreds.
Talks finally resumed Wednesday after intense mediation by Ethiopian and African Union envoys, who have put forward a draft proposal to break the deadlock.
The two sides were due to meet again on Thursday evening.
"The discussion will be about who heads the sovereign council," a prominent protest leader who is part of the talks, Ahmed al-Rabie, told AFP, referring to the governing body.
He said the ruling military council that took power after Bashir's ouster insists the head of the new governing body be from the army.
"We believe that symbolically the head of the state must be a civilian," Rabie said.
For weeks this issue has rocked Sudan, extending the political crisis triggered since the fall of Bashir.
The joint Ethiopian and African Union blueprint calls for a civilian-majority ruling body.
On Wednesday, the first day of the latest round of talks, the two sides did not discuss the crucial issue of the governing body.
"The parties conducted responsible negotiations and agreed on some issues," African Union mediator Mohamed El Hacen Lebatt told reporters overnight after long hours of talks held at a luxury hotel in the capital.
"There's a decision taken to release all political detainees."
A group of 235 fighters from a faction of a Darfur rebel group that is part of the protest movement were released later on Thursday.
They were freed from Al-Huda prison in Omdurman, the twin city of Khartoum across the Nile river, an AFP correspondent reported, adding that many relatives had arrived to receive the fighters.
Protest leaders have exerted pressure on the generals since the June 3 raid on the mass sit-in outside army headquarters.
The raid was carried out by men in military fatigues.
The ruling military council insists it did not order the violent dispersal of the sit-in.
At least 136 people have been killed across the country since the raid, including more than 100 on June 3, according to doctors close to the umbrella protest movement, the Alliance for Freedom and Change.
The health ministry says 78 people have been killed nationwide over the same period.
On Sunday, protest leaders managed to mobilise tens of thousands of supporters in the first mass protest against the generals since the raid.
The mass rally had been seen as a test for the protest leaders' ability to mobilise crowds after the generals imposed a widespread internet blackout and deployed security forces in the capital's key squares and districts, its twin city Omdurman and other towns and villages. 
Protest leaders have further upped the pressure on the generals by calling for a similar mass protest on July 13, to be followed by a nationwide civil disobedience campaign a day later.
The campaign, if observed, would be the second such agitation since the June 3 raid.
The first, held between June 9 and 11, paralysed the country, hitting an already dilapidated economy hard.
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