Mohamed Hamdan Dagalo, deputy chief of Sudan's ruling military council, leads the Rapid Support Forces (RSF) that protesters say is responsible for a "bloody massacre" that has left at least 60 people dead.

"We will not allow chaos... we must impose the authority of the state through law," the commander, known as Himediti, told troops in a televised address.

The general singled out makeshift barricades erected across streets by demonstrators that are aimed at blocking the security forces.

The RSF are paramilitary groups with origins in the Janjaweed militia accused of abuses during the 16-year-old conflict in Darfur.

Security forces on Monday moved in to brutally disperse a sit-in outside army headquarters in Khartoum that was demanding a handover to civilian rule.

Sudan's military council has controlled the country since ousting veteran president Omar al-Bashir in April after months of protests against his authoritarian rule.

It has now ditched an agreement for a three-year transition period to a civilian administration and instead is pushing for an election to take place in nine months.