The ICRC said on Thursday that 111 people were killed in Khartoum alone. Sudan's southern capital of Juba has also seen days of violence that left dozens dead.
Meanwhile, fighters from late Sudanese vice president John Garang's ex-rebel group have entered the capital of south Sudan for the first time as part of a massive joint operation with the government to secure the restive town for his weekend funeral, officials and residents said on Thursday.
Up to 1000 soldiers from the Sudan People's Liberation Movement/Army (SPLM/A) arrived in Juba late on Wednesday.
At the SPLM/A base in New Site, southeast of Juba, an AFP reporter saw dozens more heavily armed ex-rebels waiting to board planes for Juba, which under a landmark January peace deal is to serve as capital of autonomous southern Sudan.
Juba resident Samson Fadhali Samuel told reporters former rebel fighters had helped quell widespread looting at a Juba market that was dominated by northern Sudanese Arab traders many of whom have since fled.
A Khartoum-based trader
waiting to leave Juba
Juba, a garrison town for the Sudanese military that is home to between 40,000 and 80,000 government troops, was never taken by the SPLM/A during the 21-year north-south civil war that ended in January.
Also on Thursday, Sudanese President Omar al-Beshir issued a decree appointing Salva Kiir as first vice president and head of the autonomous administration for southern Sudan, the official SUNA news agency said.
Kiir had been named as Garang's successor as leader of the SPLM/A on Monday.
Garang died in a helicopter crash on Saturday less than a month after being sworn in as first vice president under a landmark January peace deal that ended two decades of civil war.