Leaders of the protests in the Sudanese capital Khartoum have called on supporters to stay in the streets two days after the military coup.
They are demanding an immediate move to civilian rule after the army ousted long-time leader Omar al-Bashir, putting him in custody.
The military wants to hold power for two years, followed by elections.
It replaced its own leader in an apparent concession to the protesters but the change did not sway them.
“We call on the armed forces to ensure the immediate transfer of power to a transitional civilian government,” the Sudan Professionals Association (SPA), which has been spearheading the demonstrations, said on Facebook.
A growing economic crisis has gripped the country since the oil-rich southern part split away in 2011, and Thursday’s coup followed months of unrest over the cost of living.
When Mr Bashir was removed, he was replaced by a military council led by Defence Minister Awad Ibn Auf.
But demonstrators camping out outside army headquarters in Khartoum refused to disperse, rejecting Mr Ibn Auf as an ally of Mr Bashir.
On Friday, the new leader announced he was resigning and being replaced by Lt-Gen Abdel Fattah Abdelrahman Burhan, who is seen as a less controversial figure.
But the move failed to satisfy protesters who have kept up their sit-in in the capital.
They called for the abolition of “arbitrary decisions by leaders that do not represent the people” and the detention of “all symbols of the former regime who were involved in crimes against the people”.
“Until these demands are fully met, we must continue with our sit-in at the General Command of the Armed Forces,” the SPA said.
At least 16 people have been killed by stray bullets at the protests since Thursday, police say.