Anti-government protestors blocked roads in Khartoum on Friday to protest against an outburst of violence the day before that left five people dead and prompted a wave of condemnations.
On Thursday, the repression by the authorities reached a new level.
First, the security forces cut off mobile internet, all telephone communications -- including calls from abroad - and the bridges linking Khartoum to its suburbs, Omdourman and Khartoum-North.
In the streets of the capital and its outskirts, security forces fired tear gas and live ammunition at tens of thousands of supporters of civilian rule in a country that has been under military rule for most of its 65 years of independence.
At the same time, officers arrested journalists and attacked the office of the Arab satellite channel al-Arabiya.
After two months of a crackdown that has left a total of 53 people dead, the violence on Thursday was concentrated in Omdurman, where four protesters were fatally shot in the head or chest, according to a pro-democracy doctors' union.
A fifth died on Friday after being shot on Thursday in central Khartoum.