Garang's death would be considered a heavy blow to the January peace deal that ended a 21-year civil war between the mostly Muslim north and the Christian and animist south in which some 2 million people died.
So far, there does not appear to be any word of foul play. However, as we all know, "helicopter crashes" are a common way of assassinating political opponents in the Middle East. I hope that's not the case, because if it is, Sudan could erupt into major bloodshed once again. Also from the AP article:
There is no other leader of Garang's stature in the former rebel movement, the Sudan People's Liberation Army, which he founded and dominated for 21 years. His arrival in Khartoum on July 8 to take the vice president's post brought millions of southerners and northerners to the streets in celebration.
His flight's disappearance evoked memories of the 1994 downing of the airplane of Rwandan President Juvenal Habyarimana, who had been trying to implement a power-sharing deal between his fellow Hutus and the rival Tutsis. His death opened the doors to the Rwandan genocide in which more than 500,000 people were killed, following months of preparation by Hutu extremists.
Oh, and Sudan also has oil, with production expected to reach 500,000 barrels per day in 2005, having increased as a result of the December 2004 Comprehensive Peace Agreement ending Sudan's civil war.
In other words, watch out!
[UPDATE 7:06 AM - Just as I warned, violence has now broken out, with "Thousands of southern Sudanese wielding knives and bars have looted shops and clashed with police in the streets of Khartoum after learning of the death of ex-rebel leader John Garang."]