Tributes have been paid to former rebel leader John Garang at his funeral in southern Sudan, attended by thousands of mourners including African leaders.
Leaders from Kenya, Uganda and South Africa attended the funeral
President Omar al-Bashir pledged that Sudan's peace process would be implemented to the letter.
Mr Garang died three weeks after he became vice-president as part of a deal to end decades of conflict. His death sparked riots that left 130 dead.
An independent investigation into the cause of the crash is to be launched.
Ugandan President Yoweri Museveni, who owned the helicopter Mr Garang was travelling in, said on Friday that the cause was not clear.
For more than 20 years, Mr Garang led the southern rebels in a civil war against the government and was seen as a symbol of hope by many in the south.
Mr Garang's body arrived in the main southern town of Juba on Saturday after being taken to a number of towns in the mainly Christian and animist south to allow thousands to pay their respects.
The airport was guarded by a mix of soldiers from Mr Garang's Sudan People's Liberation Army and their former enemies, Khartoum-based elite Sudanese government special forces.
An honour guard carried the coffin off the plane as dignitaries looked on.
Burial in Juba is a symbolic move
Mourners with black flags lined the streets from the airport and large crowds gathered outside Juba's main church for the open-air funeral.
Mr Garang's successor, Salva Kiir, assured mourners that the ex-rebel leader's vision of peace would not be allowed to perish.
"As sure as day follows night, the torch he has kindled shall not be extinguished. Not under my command," Mr Kiir said.
Mr Garang's widow Rebecca spoke of her pride in her husband, and urged people to remain united behind the peace accord.
The BBC's Peter Greste says burial in Juba, which Mr Garang's rebels tried but failed to take from rebel forces during the conflict, is a hugely symbolic move.
However in recent days thousands of Arab northerners have left Juba after riots destroyed many of the town's mostly Arab-owned shops and businesses.
Mr Garang steered the rebels through a bloody war against the Islamic government in Khartoum, which left at least 1.5 million people dead.
Garang fought for more than 20 years
He ruled the group with an iron hand, imprisoning or killing anyone who threatened to stand in his way.
But he managed to keep the disparate movement together, despite many disagreements.
The conflict in Sudan ended with the signing of a peace agreement in January and Mr Garang became vice-president in a new government of national unity.