Sudan's security forces clashed Thursday with protesters furious over a military coup that has derailed a transition to democracy, as US President Joe Biden joined an international chorus of condemnation against the takeover.

At least one protester was killed, according to medics, on the fourth consecutive day of street violence in Khartoum, where security forces reportedly used tear gas and rubber-coated bullets against demonstrators.

In this file picture taken on October 21, 2021, Sudanese demonstrators raise national flags as they take part in a protest in the city of Khartoum Bahri to demand the government's transition to civilian rule
In this file picture taken on October 21, 2021, Sudanese demonstrators raise national flags as they take part in a protest in the city of Khartoum Bahri to demand the government's transition to civilian rule AFP / -

It came as Biden and the UN Security Council called for a restoration of the civilian-led government toppled by the army early this week.

"Our message to Sudan's military authorities is overwhelming and clear: the Sudanese people must be allowed to protest peacefully and the civilian-led transitional government must be restored," Biden said in a statement.

Map of Sudan locating the capital Khartoum
Map of Sudan locating the capital Khartoum AFP / Sophie RAMIS

The Security Council unanimously expressed "serious concern" about the army's power grab in the poverty-stricken Northeast African nation, while urging all sides "to engage in dialogue without pre-conditions".

General Abdel Fattah al-Burhan -- Sudan's de facto leader since the 2019 ouster of veteran autocrat Omar al-Bashir after huge youth-led protests -- on Monday dissolved the country's fragile government and ordered the arrest of several top officials.

Sudanese protesters burn tyres to block a road in 60th Street in the capital Khartoum, to denounce overnight detentions by the army of members of Sudan's government, on October 25, 2021. Armed forces detained Sudan's Prime Minister over his refusal to sup
Sudanese protesters burn tyres to block a road in 60th Street in the capital Khartoum, to denounce overnight detentions by the army of members of Sudan's government, on October 25, 2021. Armed forces detained Sudan's Prime Minister over his refusal to support their "coup", the information ministry said, after weeks of tensions between military and civilian figures who shared power since the ouster of autocrat Omar al-Bashir. AFP / -

Prime Minister Abdalla Hamdok is under effective house arrest while the capital has been rocked by days of unrest and is bracing for major demonstrations on Saturday.

Roads have been blocked by barricades of rocks, debris and burning car tyres that have sent black smoke billowing into the sky, while most shops have been shuttered in a campaign of civil disobedience.

Sudanese protesters place bricks across a street in the capital Khartoum
Sudanese protesters place bricks across a street in the capital Khartoum AFP / -

"We do not want military power, we want a free democratic life in this country," said one protester, who asked not to be named.

Sudanese protesters lift national flags as they rally on 60th Street in the capital Khartoum
Sudanese protesters lift national flags as they rally on 60th Street in the capital Khartoum AFP / -

The latest street clashes on Thursday rocked the restive eastern Khartoum district of Burri and the Khartoum-North suburb, AFP reporters said.

Sudanese General Abdel Fattah al-Burhan has dissolved the government and the ruling sovereign council
Sudanese General Abdel Fattah al-Burhan has dissolved the government and the ruling sovereign council Sudan TV / -

At least one protester was killed in the clashes in Khartoum-north, a doctor's committee linked to the protest movement said, while six others were wounded.

Security forces fired tear gas and rubber-coated bullets at the protesters, AFP reporters said.

Sudanese security forces have deployed on the streets of Khartoum
Sudanese security forces have deployed on the streets of Khartoum AFP / -

That takes to eight the number of protesters killed since Monday's coup, up from a toll of seven given by health officials earlier in the day. Some 170 have been wounded.

The coup was the latest to have hit the country which has experienced only rare democratic interludes since independence in 1956.

Sudanese residents from the capital Khartoum call for the return of a civilian government.
Sudanese residents from the capital Khartoum call for the return of a civilian government. AFPTV / STRINGER

The World Bank and the United States have frozen aid and deplored the army's power grab, while the African Union has suspended Sudan's membership over what it termed the "unconstitutional" takeover.

Biden on Thursday also echoed the EU, Britain and others saying the events of recent days were "a grave setback" for Sudan.

He urged military leaders to "immediately release all those detained" and demanded that "the Sudanese people... be allowed to protest peacefully".

Sudan had been ruled since August 2019 by a joint civilian-military council, alongside Hamdok's administration, as part of a transition to full civilian rule.

Recent years saw the country -- formerly blacklisted by the US as a "state sponsor of terrorism" -- make strides toward rejoining the international community, unlocking aid.

But analysts said the civilians' role receded before the coup, which experts view as the generals' way of maintaining their long-held grip on the country.

Recalling the mass protests of 2019, Sudan's pro-democracy movements have called for "million-strong protests" on Saturday, further heightening tensions.

One protester Thursday described the cat-and-mouse game with security forces, saying that they "have been trying since yesterday morning to remove all our barricades, firing tear gas and rubber bullets".

"But we go and rebuild them as soon as they leave," added the activist, Hatem Ahmed, from Khartoum. "We will only remove the barricades when the civilian government is back."

Burhan, a senior general during Bashir's three-decade-long hardline rule, has sacked six Sudanese ambassadors -- including to the US, EU, China and France -- who have criticised his actions.

Foreign Minister Mariam al-Sadiq al-Mahdi -- whose father was the prime minister ousted by Bashir's 1989 coup -- is one of the few civilian leaders not in detention and has become a leading voice of criticism.

Sudan's state television meanwhile reported Thursday that its head Luqman Ahmed, a veteran advocate of civilian rule, had been sacked.