Doctors in Sudan say nine protesters have so far died following protests against military rule.
Many of the victims according to doctors had been shot by security forces who had confronted large crowds in multiple cities.
There were instances where the military tried to break into hospitals where some of the injured were being treated.
During Thursday’s demonstration, protesters barricaded roads, waved placards and chanted slogans calling on the military to leave power.
Police then used tear gas, water cannon and live ammunition to control the swelling crowds from marching towards the presidential palace in Khartoum.
Earlier the UN envoy to Sudan, Volker Perthes was summoned by the military leaders over remarks he made regarding the anti-military protests.
Mr Perthes has been at loggerheads with the military authorities since the coup against the civilian-led transitional government last October.
In an interview on Wednesday with Saudi-funded Al-Hadath TV the envoy cautioned the government and security agencies to maintain the right of freedom of expression and the right for assembly.
He said authorities “should avoid using excessive force and violence against the protesters”.
In a statement on Twitter, Mr Perthes had said “violence against protesters will not be tolerated” while calling for the authorities to “ensure their commitment to protecting the rights” of the people.
Earlier, internet and telephone services were cut off as the authorities attempted to stop the online mobilisation of protesters.
Protests erupted in Sudan last October after the military toppled a civilian-led transitional government.
Thursday’s protests were the largest to be held in the country since the coup.
They coincided with the third anniversary of huge demonstrations that overthrew long-time autocratic ruler Omar al-Bashir.