Huge crowds have marched on Sudan's defence ministry demanding the ruling military hand over power to civilians, in protests that saw at least seven people killed and scores injured nationwide.

Key points: Authorities said that seven people were killed and 181 injured in the protests

Authorities said that seven people were killed and 181 injured in the protests Sudan's army ousted the country's president after months of demonstrations

Sudan's army ousted the country's president after months of demonstrations Civilians are now calling for the military to relinquish power

In the biggest demonstrations since a deadly raid by security forces on a protest camp in central Khartoum three weeks ago, tens of thousands of residents took to the streets in several parts of the Sudanese capital.

In two areas near the presidential palace and in the upscale eastern neighbourhood of Riyadh, they were met by security forces firing barrages of tear gas, witnesses said.

The deputy head of Sudan's ruling military council, General Mohamed Hamdan Dagalo, known as Hemedti, said unknown snipers were shooting at civilians and soldiers.

Sudanese civilians have been calling for a transition to democracy for months. ( AFP: Ahmed Mustafa )

Seven people were killed and 181 injured, 27 of those wounded by live fire, the state news agency reported, citing a Health Ministry undersecretary.

The official said 10 of those injured were members of regular forces, including three conscripts of the Rapid Support Forces (RSF), led by Hemedti, who were injured by gunfire.

The remaining seven were injured by stones hurled by demonstrators, he added.

Sudan's military overthrew president Omar al-Bashir in April after months of demonstrations against his rule.

Opposition groups kept up those demonstrations as they pressed the military to hand over power to civilians.

But talks broke down after members of the security services raided the sit-in protest camp outside the defence ministry on June 3.

Sunday was the 30th anniversary of the coup that brought Mr Bashir to power and marked the African Union's deadline for Sudan's military rulers to hand over to civilians or face further sanctions.

Hundreds of Sudanese protesters have been killed in the unrest. ( AFP: Ahmed Mustafa )

'We will not retreat'

In another part of Khartoum, thousands blocked the main multi-lane highway that leads to the airport as they marched toward the home of a protester who was killed in January.

Protesters waved the Sudanese flag and chanted "civilian, civilian" and "blood for blood", as officials beefed up security across the capital.

"We came out once again for the revolution and we will not retreat until they handover power to a civilian authority," protester Hassan Ahmed said.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 6 minutes 59 seconds 6 m Sudan's autocratic neighbours want protests to fail. ( The World )

The Transitional Military Council had warned a day earlier that the opposition coalition would bear the responsibility for any loss of life or damage resulting from Sunday's protests.

Members of one of the main opposition groups — the Sudanese Professionals' Association — said the security services raided its headquarters on Saturday night as it was about to give a news conference.

The United Nations has said it has received reports that more than 100 protesters were killed and many more injured during the June 3 raid on the protest camp.

Military leaders have denied ordering a raid on the camp and said a crackdown on criminals nearby had spilled over.

The council has said some officers had been detained for presumed responsibility, and that it still intends to hand over power after elections.

Reuters