World Bulletin/News Desk

Sudanese police on Friday released 17 senior members of the opposition Umma Party who were briefly detained for participating in a protest in capital Khartoum to demand the release of two opposition leaders arrested earlier, including Umma Party leader Al-Sadeq al-Mahdi.

A security source said the 17 party members, including al-Mahdi's son and four daughters, were all released after signing pledges not to take part in any unauthorized protests.

The authorities also released Mondher Abu al-Maali, a senior member of the opposition Nasserist Arab Socialist Party, and Unionist Movement leader Ahmed Khedra. Both men had been detained from their homes shortly before Friday's demonstration.

According to Intisar al-Aqali of the Nasserist Arab Socialist Party, the pair has since been released and returned to their homes.

Sudanese security forces had arrested the opposition activists earlier in the day before and during the Khartoum demonstration, which was held to demand the release of both al-Mahdi and Ibrahim al-Sheikh, leader of the opposition Sudanese Congress Party.

An Anadolu Agency correspondent reported that security forces had arrested al-Mahdi's son and four daughters – Mohamed, Um Salma, Mariam, Rabah and Zeinab – during Friday's protest dispersal.

Hundreds took part in the protest march, which set out from northern Khartoum's Shambat district following weekly Friday prayers.

They marched to the nearby Rabtah Square before being intercepted by teargas-firing police.

The Sudanese Congress Party's al-Sheikh was arrested last week in the town of En Nahud in West Kordofan State. He currently faces multiple charges, including incitement to violence and undermining the constitutional regime – both of which are punishable by death.

Al-Mahdi, meanwhile, was arrested last month for allegedly "defaming" the country's security and intelligence apparatuses.

Al-Mahdi's Umma Party linked the 78-year-old veteran politician's arrest to his recent criticisms of Sudan's security agencies, which he had earlier blamed for violence in Darfur.

Al-Mahdi dismisses the charges against him as "null and void."

The latest crackdown comes after tensions had appeared to ease between opposition forces and President Omar al-Bashir – who overthrew al-Mahdi's elected government in 1989 – after al-Bashir invited the opposition to take part in a round of national dialogue.

In recent months, opposition figures have criticized the deployment of Sudanese police to fight alongside army forces in Darfur.

Darfur rebel groups, for their part, accuse Sudanese security forces of carrying out attacks based on ethnicity.