CAIRO — Hundreds of protesters took to the streets in Sudan's capital and across the country on Sunday, demanding the disbanding of the former ruling party that underpinned Sudanese President Omar al-Bashir's three decades in power.

The demonstrations were organized by local groups linked with the Sudanese Professionals' Association, which spearheaded the uprising that toppled al-Bashir in April. Protests continued throughout the summer, despite a violent clampdown by the country's security forces, forcing the ruling generals into a power-sharing agreement with civilians.

In the capital of Khartoum, the protesters also called on authorities to step up an investigation into the hundreds of people who went missing on June 3, when security forces dispersed the main sit-in outside the military headquarters. According to the protesters, at least 128 people were killed and hundreds went missing. Authorities put the death toll at 87, including 17 inside the sit-in area.

Dura Gambo, an activist with the SPA, said the demonstrators wanted to know the fate of those who disappeared in the June crackdown.

"If they are alive, where are they, and if they were dead, where are their bodies? This what we want to know," she said.

The protesters carried posters of the missing people, and marched to the office of the country's chief prosecutor, where they presented officials with written demands for a new investigation by an independent committee.

Protesters already rejected the results of the prosecutor's investigation in September, which said the country's ruling generals did not order the deadly break-up, and blamed the deaths on paramilitary forces who exceeded their orders.

Setting up an independent probe into the crackdown was a key point in the transition deal between the military and civilian leaders signed in August. The new government has just over three years to steer the country toward democratic elections.

Sunday's rallies also took at aim at the lingering influence of al-Bashir's political system, including his National Congress party.

Footage circulated online showing the protesters, mostly youth, in the city of Wad Madani, the provincial capital of al-Jazirah province, waving Sudanese flags and calling for the former ruling party's dissolution as well as resignation of the local governor whom al-Bashir appointed.

There were no reports of any clashes with police or casualties during the protests.

The transitional government previously said it won't appoint governors or an interim parliament until it makes peace with the country's rebel groups.

The first round of peace talks between government and the rebel leaders took place in October in South Sudan's capital, Juba, and are to resume later this month.

Separately on Sunday, the Sudan Liberation Movement/Army said its forces repelled an attack by the Sudanese military the previous day on areas under its control in South Darfur province, killing at least 36 troops.

Spokesman Waleed Mohammed Abkar said in a statement they also wounded at least 134 government forces, and seized weapons including RPGs and rifles, along with large amounts of ammunition.

He said a rebel leader was killed and three rebels were wounded in the attack.

The group posted photos alleging to show the dead soldiers in military uniform and with their military IDs.

There was no immediate comment from the Sudanese military and a government spokesman did not answer phone calls seeking comment.

The rebel group is led by Abdel Wahid al-Nur and it has rejected the transitional government, staying out of the peace talks held in Juba.