Sudanese authorities Tuesday ordered all schools nationwide to suspend classes indefinitely after crowds of students launched demonstrations against the killing of six protesters including five pupils at a rally in a central town.
"Killing a student is killing a nation," chanted hundreds of schoolchildren, dressed in their uniforms and waving Sudanese flags, as they took to the streets of Khartoum against the killings in Al-Obeid on Monday.
Sporadic protests by schoolchildren were also held in other parts of the capital and in other cities.
Five high-school students were shot dead and more than 60 wounded, some by snipers, when they rallied in Al-Obeid against fuel and bread shortages, the protest movement and residents said.
Late on Tuesday, a doctors committee close to the protest movement said a sixth protester died of wounds after he was "shot with a bullet in the head".
The committee did not say if he too was a student.
Demonstrators accused feared paramilitaries of the Rapid Support Forces (RSF) of shooting dead the teenagers.
On Tuesday, the authorities ordered all schools nationwide to suspend classes.
"Orders have been given to governors of all states to shut kindergartens, primary and high schools from tomorrow (Wednesday) until further notice," the official SUNA news agency said, following a directive issued by the ruling military council.
The killings came a day before protest leaders were due to hold talks with generals on remaining aspects of installing civilian rule after the two sides inked a power-sharing deal earlier this month.
But protest leaders called off Tuesday's meeting.
"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," said a negotiator and prominent protest leader, Satea al-Haj.
The chairman of Sudan's 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," he told journalists, quoted by state television.
Later on Tuesday in an interview with state television Burhan called on negotiators from both sides to "expedite" the dialogue given the overall impasse in the country.
On the streets, crowds of students rallied in Khartoum waving 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 UN children's agency Unicef called on the authorities "to investigate" the killings and hold the perpetrators accountable.
Authorities announced a night-time curfew in four towns in North Kordofan following the deaths in Al-Obeid, as the main protest group, the Sudanese Professionals Association, called for nationwide rallies against the "massacre".
"The Janjaweed forces and some snipers, without any mercy, confronted school students with live ammunition," the SPA said, referring to the RSF which has its origins in Arab militias that were originally deployed to suppress an ethnic minority rebellion that erupted in Sudan's western region of Darfur in 2003.
Burhan defended the RSF as "a systematic force that was part of the armed forces".
Doctors linked to the protest movement say more than 250 people have been killed nationwide in protest-related violence since December when demonstrations first erupted against now ousted president Omar al-Bashir.
Tuesday's talks were to cover issues including the powers of the joint civilian-military ruling body, the deployment of security forces and immunity for generals over protest-related violence, according to protest leaders.
The power-sharing deal agreed on July 17 calls for the establishment of a new governing body of six civilians and five generals.
But the publication on Saturday of the findings of an investigation commissioned by the military into the deadly dispersal of a Khartoum protest camp in June also triggered angry demonstrations.
Shortly before dawn on June 3, gunmen in military fatigues raided the site of a weeks-long sit-in outside army headquarters, shooting and beating protesters.
Doctors linked to the protests say the raid left 127 people dead and scores wounded.
Protest leaders have rejected the findings of a joint investigation by prosecutors and the military council which concluded that just 17 people were killed on June 3, with a total of 87 deaths between that day and June 10.
Burhan said there was "no interference" in the raid's investigation, which prosecutors conducted independently.
"No one from the military council knew or ordered the dispersal of the sit-on," he added.