The number of people killed in Sudan has risen to 60, an opposition doctors' group says, as paramilitary forces push deeper into Khartoum.
The revised death toll came after two days of unrest which began when forces of the Transitional Military Council (TMC) fired on unarmed protesters.
Members of a feared paramilitary group have reportedly been roaming the streets attacking civilians since.
The military has faced international condemnation for the deadly crackdown.
However, an attempt by the UK and Germany at the UN to call on the Sudanese military to work towards finding a solution was blocked by China, who were backed by Russia.
Demonstrators had been occupying the square in front of the military headquarters since April 6, five days before President Omar al-Bashir was overthrown after 30 years in power.
Their representatives had been negotiating a deal with the TMC, and had agreed a three-year transition, culminating in elections.
But on Monday, forces moved in to forcibly move the protesters from the square.
Many Khartoum residents blamed the Rapid Support Forces for the crackdown. The paramilitary unit - formerly known as the Janjaweed - gained notoriety in the Darfur conflict in western Sudan, which began in 2003.
The TMC then announced polls would be held within nine months. The demonstrators had argued that a longer period was needed in order to guarantee fair elections and dismantle the political network associated with the former government.
The protesters had called for the Islamic festival of Eid al-Fitr, marked on Tuesday and Wednesday this week, to be celebrated in the streets, as a gesture of defiance against the military.
On Tuesday, however, much of Khartoum seemed to be under lockdown. Video shot on mobile phones showed columns of troops advancing along the streets, removing barricades and firing into the air.
One resident, who wanted to remain anonymous for her own safety, told the BBC of a city in fear as reports of atrocities spread.
Her uncle had witnessed three young men being executed in the city, she said.
"We're living like hostages, no one can get out," she said, adding that the internet is blocked.
Flights into Khartoum have also been disrupted.
Large numbers of heavily armed troops were also reported on the streets of Omdurman, Sudan's second-largest city, just across the River Nile from Khartoum.
A woman, identified only as Sulaima, told the BBC that troops from the Rapid Support Forces were "all over Khartoum".
"They're surrounding neighbourhoods, they're threatening people. They're also using live ammunition. They're everywhere. We're not feeling safe and we don't have trust in the security forces. It's complete chaos."
Earlier, Gen Abdel Fattah al-Burhan, the TMC head, said on state television the council had decided to "stop negotiating" with the protesters and "cancel" all previous agreements, and that an election would be held in nine months.
The US, the UK and Norway expressed "serious concern" over the announcement, and called for "an agreed transfer of power to a civilian-led government".