Protesters waved the Sudanese flag and chanted "civilian, civilian" and "blood for blood” in Khartoum during the “millions march.”

Tens of thousands of people took to the streets in Khartoum Sunday demanding the military hand over power to civilians, in the largest demonstrations since a deadly security service raid on a protest camp three weeks ago which is being called as the “June 3rd massacre.”

Protesters waved the Sudanese flag and chanted "civilian, civilian" and "blood for blood" in several parts of the capital as security forces looked on during the “millions march.” Opposition groups posted videos of what they said were rallies in other cities.

Sudan’s military rulers overthrew long-time President Omar al-Bashir on April 11 after months of demonstrations against his rule. Opposition groups kept up their streets protests as they pressed the military to hand over government affairs to civilians. The June 30 protest coincides with the 30th anniversary of the 1989 coup by al-Bashir.

"The current coup is the continuation of the same one that happened 30 years ago. These people are not different at all. Their policies, their practices, the way they deal with civilians is the same. Their abuse of human rights, denial of democratic transformation of the country - it's no different at all. It's just like al-Bashir is in action right now," said Ahmed H Adam, a researcher at SOAS's School of Law.

Talks broke down and protests paused after security services raided a sit-in protest outside the defense ministry on June 3. But there has been a run of smaller demonstrations in recent days, and the Forces for Freedom and Change (FFC) opposition coalition called for a million people to turn out Sunday.

Protests have been planned in major cities around the world such as Washington, London, Dublin, Kuala Lumpur, etc., in solidarity with Sudanese protesters.

"Not being in Sudan at times like this make the youth of the diaspora feel helpless. Protests outside of Sudan gives them hope and a feeling of belonging and as they fight a different fight on the outside; this is their revolution too," Ehab Eltayeb from Texas told Al Jazeera.

There was no immediate comment from the ruling military council which had warned a day earlier that the coalition would bear the responsibility for any loss of life or damage resulting from the rallies.

Members of one of the main opposition groups - the Sudanese Professionals' Association - said security services raided its headquarters 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 more than 500 injured at the sit-in protest on June 3 according to the Central Committee of Sudanese Doctors (CCSD) while the Health Ministry said that death toll was at 61.

Military leaders have denied ordering a raid on the camp and said a crackdown on criminals nearby had spilled over to the sit-in. The council has said some officers had been detained for presumed responsibility and it still intends to hand over power after elections.

Mediators led by the African Union and Ethiopian Prime Minister Abiy Ahmed have since been trying to broker a return to direct talks.