Garang's body is to be carried in a procession from town to town through his stronghold ahead of a funeral on Saturday in Juba, the city that became the capital of autonomous south Sudan under the peace agreement he helped craft.
Heavily-armed Sudanese police and soldiers were patrolling Khartoum and Juba after three days of rioting in the Sudanese capital and the flashpoint southern town that left more than 100 people dead and sent many more fleeing to safety.
Appeals for peace
The international community has issued urgent appeals for calm, fearing that the death of the former rebel leader could plunge Africa's largest country into fresh turmoil and undermine the January deal that turned the page on 21 years of north-south war.
In a bid to ease tensions, Sudanese President Omar al-Beshir announced on Wednesday the launch of a committee to investigate Garang's death, which many of his supporters claim was not an accident.
Garang's successor, Kiir, has
called for calm
Washington urged the government to do more to halt the violence that has pitted southerners against northern Muslims, while UN Secretary-General called on all Sudanese to show restraint.
International diplomats were dispatched to the country to shore up the north-south peace process in Sudan, which is also torn by conflicts in the western region of Darfur and in the eastern Red Sea state.
The International Committee of the Red Cross said 84 people had been killed since rioting broke out on Monday in Khartoum, where security forces in army personnel carriers and pickup trucks carrying machine guns were patrolling the streets to keep fighting at bay.
At least 18 people have also been killed and hundreds wounded in Juba, where thousands of northern Sudanese have also reportedly fled in fear of their lives, witnesses said.
Fighting in Juba and Khartoum
has killed more than 100
Witnesses recounted a day of clashes in Juba, saying southern Sudanese burned and looted businesses owned by Arabs considered close to the Muslim government in Khartoum.
"They burnt down our shops and homes and we had no choice but to find safety," one trader told AFP at Juba airport where a sea of people dozed on boxes and nylon sacks filled with their belongings.
Large number of heavily-armed Sudanese troops patrolled Juba as the town prepared for Saturday's funeral, expected to be attended by more than 50,000 mourners.
Salva Kiir, Garang's replacement as head of the Sudan People's Liberation Movement/Army (SPLM/A) joined international calls for an end to the bloodshed.
"Enemies of peace may want to take the opportunity of the situation so that they don't allow the government and the SPLM to implement the peace agreement," he said.
Sone fear the violence could
jeopardise the peace process
"We want this situation to be stopped as soon as possible so that security returns to Khartoum and its suburbs."
Calm had returned to the capital by Wednesday night, mostly owing to what city governor Abd al-Halim Mutaafi said was the "largest deployment of security organs in Khartoum's history."
He said hundreds had been arrested during the riots. Several residents said the deadly clashes had taken place in the southern-majority neighbourhood of al-Haj Yusif and the situation remained extremely tense.
The United States, which invested much political capital into securing the 9 January pact, and others are concerned the agreement may unravel despite vows from both Kiir and Khartoum to uphold it.
"We urge the government of national unity to continue to take steps to stop the violence, to promote reconciliation and to maintain momentum on implementation of the comprehensive peace agreement," acting State Department spokesman Tom Casey said.
The SPLM/A appointed Kiir, Garang's longtime deputy, to take over his duties as the group's leader and the posts of first vice-president of Sudan and president of an autonomous southern Sudan.
Garang had assumed the government positions just three weeks before his death, under the terms of the January pact, which calls for southern Sudan to enjoy six years of autonomy under a national unity government, followed by a referendum on secession.