The trial of four Sudanese protesters accused of killing a police officer began in Khartoum on Sunday amid anti-military demonstrations and a heavy police presence.
The four, accused of the fatal stabbing of a police brigadier-general in January, were seen by a Reuters witness entering the courtroom in Khartoum, raising their fists and making victory signs.
The defendants, who have become emblems of the anti-military protest movement, deny the charges.
Security forces have frequently detained opposition politicians and figures connected to the protest movement since a coup ended a military-civilian power sharing arrangement in October. Lawyers say dozens remain in detention.
On Sunday, a security body attached to Sudan's ruling council recommended lifting an emergency law imposed after the coup and releasing those arrested under it.
The ruling council said the move was meant to create conditions for dialogue. Efforts to break the deadlock between the military and its opponents have so far made little progress.
Relatives and lawyers for the men whose trial started on Sunday have accused authorities of torturing at least one of them, known by his nickname Tupac.
Police couldn't be reached for comment, while military leaders deny the accusations.
Abdelazim Hassan, part of the legal team representing the men, said the judge hearing the case ordered that the men undergo a medical examination.
Sudanese military leaders have said the men are subject to normal criminal procedures.
Outside the courtroom protesters chanted: "Tupac is not a killer," and "Burhan is a killer," referring to General Abdel Fattah al-Burhan who led an October coup.
There have been weekly mass protests against the coup, which ended two years of power sharing following the ouster of Omar al-Bashir. The military says it intervened because of political paralysis to "correct" the transition.
Two protesters were killed on Saturday by security forces during protests on the outskirts of Khartoum, medics said, bringing the number who have died in the protests to 98.
"We will not be ruled through fabricated charges, and we will not be ruled by murder," said Hamza, a protester at the courthouse.