A Sudanese court on Wednesday sentenced 11 members of the Darfur rebel Justice and Equality Movement to death for a 2008 attack on the Sudanese capital.

Five other defendants were acquitted and will be freed, the court said.

More than 70 rebels have now been sentenced to death for the bold attack in which more than 200 people were killed, including JEM leader Khalil Ibrahim's half brother Abdel Aziz el-Nur Ashr. None of those sentenced has yet been executed.

The rebels drove hundreds of miles across desert and scrubland to reach the capital and were only a few kilometres from the presidential palace when government troops halted them.

"We sentence them to the death penalty by hanging," judge Issam Ismail said on Wednesday after the individual verdicts were read out, to shouts of protest from the condemned men.

The men were found guilty of 12 charges, including treason, violence against the state and illegal possession of weapons.

Their lawyer launched an appeal against the verdict and questioned the legality of the specially created terrorism courts.

"I have appealed, but the procedures of this court are against the rules of justice," lawyer Adam Bakr said.

"This court is against the Sudanese constitution's article 34," he added, referring to the guarantee of a fair trial.

The court in Omdurman is housed in a compound JEM rebels fired missiles at during the attack on May 10 last year.

The street, a main thoroughfare in Khartoum's sister city, was blocked by a heavy security presence.

Two other cases will be transferred to another court, one because the suspect is under 18 years old, the other because the defendant was judged mentally unstable.

In a separate trial last week, 10 JEM members were sentenced to death after being found guilty of involvement in the same attack on Khartoum and three were acquitted.

JEM have refused to return to peace talks in Qatar unless all political prisoners and prisoners of war have been released.