FILE - Yasir Arman speaks during joint news conference in Khartoum, Dec. 22, 2010.

The family of the detained prominent Opposition figure in Sudan is calling for his release.

Yassir Arman was arrested on Tuesday by members of the national security service at his residence in Arkueet in Khartoum.

According to the family, masked men on three trucks loaded with heavy machinery raided the residence, and brutally beat up everyone, including Arman.

He is being held at Shendi station, an alleged ghost house operated by the regime’s security apparatus.

The family stressed that the Transitional Military Council is responsible for Yassir Arman’s arrest and his safety.

They demanded his immediate release.

Yassir Arman is a member of the opposition SPLM-North, which has been fighting Khartoum regime in Nuba Mountain and the Blue Nile regions.

He returns to Sudan recently after President Bashir was ousted two months ago.

After his arrival last month, he joined the protesters at the sit-in strike in the front of the military headquarters where they are demanding for a civil government.

On May 28, he announced on Facebook that he had received six letters from the head of TMC, Abd al-Fattah al-Burhan and his vice-president Mohamed Hamdan, asking him to leave Sudan.

In messages, the Transitional Military Council told Arman to leave Khartoum because he is not welcomed.

He rejected all these messages and commands.