Sudan's security forces have used force to try to break up a long-running sit-in outside the army headquarters in Khartoum, protesters say, ONA reports citing BBC.
There are reports of gunfire and barricades set ablaze.
Sudan has been governed by a Transitional Military Council (TMC) since President Omar al-Bashir was overthrown in a coup in April.
Protesters have been demanding that a civilian government should take over the running of the country.
"Now an attempt is taking place to disperse the sit-in," said a short statement from the Sudanese Professionals Association, the group which is spearheading nationwide protests.
Eyewitnesses say the protesters have erected barricades and set them ablaze to try to fend off the security forces.
Videos are being shared on Twitter that appear to show people who have been injured, but these have not been verified.