Sudanese protest leaders cancelled planned talks with the country's ruling generals on Tuesday as hundreds of schoolchildren demonstrated in Khartoum against the shooting dead of five pupils at a rally.
"Killing a student is killing a nation," chanted crowds of schoolchildren, dressed in their uniforms and waving Sudanese flags, in the capital's eastern district of Burri.
Sporadic protests by schoolchildren were also held in other parts of the capital.
Demonstrators accused feared paramilitaries of the Rapid Support Forces of shooting dead the five teenagers on Monday in the central town of Al-Obeid at a rally against shortages of bread and fuel.
The killings came a day before protest leaders were due to hold talks with generals on the remaining aspects of installing civilian rule after the two sides inked a power-sharing deal earlier this month.
But three protest leaders said the dialogue would not take place as planned.
"There will be no negotiations today as we are still in Al-Obeid," Taha Osman, a negotiator from the protest movement, told AFP by telephone from the town.
"There will be no negotiation today with the Transitional Military Council as our negotiating team is still in Al-Obeid and will return only tonight," a second negotiator, Satea al-Haj, said.
Another protest leader told AFP on condition of anonymity that talks would resume after "calm returns to the streets as dialogue was the only way to break the overall political impasse".
The chairman of Sudan's ruling military council, General Abdel Fattah al-Burhan, condemned the killings.
"What happened in Al-Obeid is sad. Killing peaceful civilians is an unacceptable crime that needs immediate accountability," the chairman of Sudan's ruling military council told journalists, according to state television.
Crowds of students rallied in Khartoum waving Sudanese flags and chanting: "The people want to fight for the rights of martyrs".
"We keep silent all the time and they kill us," said Enas Saifeddine, a 16-year-old high school student.
"The five students of Al-Obeid were killed because they were asking for something that is basic like food, water and electricity."