Four people have been killed in Sudan as forces loyal to the country's military rulers try to quell an opposition-backed civil disobedience campaign.

Security forces killed two people in clashes in the capital, Khartoum, where protesters erected roadblocks, and another two in the neighboring city of Omdurman, the opposition-linked Central Committee for Sudanese Doctors said Sunday.

The killings increased the death toll since a crackdown on an opposition sit-in on June 3 to 118, the organization added.

The Sudanese Professionals Association (SPA), one of the leading opposition groups, has called on people to join the civil disobedience campaign until the ruling Transitional Military Council (TMC) transfers power to a civilian government.

In Khartoum's northern Bahari district, protesters used tree trunks and rocks to build roadblocks as riot police fired into the air and used tear gas to disperse the crowd, according to a witness.

"They opened the way, we closed it again, they opened it, we re-closed it. It was a game of cat and mouse," said one protester.

Markets and shops were closed and streets remained empty in many other parts of the country.

Read more: African Union suspends Sudan, demands end to military rule

TMC wants 'consensus'

In televised comments, TMC spokesman Shams al-Deen al-Kabashi urged the protest leaders to end the civil disobedience campaign and said the council would be willing to revive talks with the opposition.

"We have no objections to getting back to negotiations and reaching consensus," al-Kabashi said.

In April, the TMC removed longtime dictator Omar al-Bashir from office and took power. The move came after months of anti-Bashir protests first launched by the SPA.

Since then, both sides have held several rounds of talks on a peaceful transition of power. The last round broke down in mid-May.

amp/cmk (AFP, AP, Reuters)

Every evening, DW sends out a selection of the day's news and features. Sign up here.