Leaders from both the north and south of Sudan have appealed for an end to clashes in the capital Khartoum.
More than 100 people have died there after violence broke out following the death of former southern rebel and peacemaker John Garang.
Angry southerners took to the streets after his death in a helicopter crash was announced.
President Omar Hassan al-Bashir made a televised appeal for calm, saying he urged “all good people to bury the strife”.
Bashir said he had established a joint committee with the Sudan People’s Liberation Movement – which Garang had led – to investigate the fatal crash. There is no suggestion of foul play.
Garang’s successor as first vice president, Salva Kiir, echoed Bashir’s call as he met foreign diplomats in a bid to maintain the fragile north-south peace pact.
In Juba, where Garang’s funeral will take place on Saturday, demonstrations have also turned violent, with at least one person killed and dozens more injured.