Sudanese authorities have arrested several top members of the former ruling party of ousted President Omar al-Bashir,, who has been stripped of millions of dollars in cash found in his home.

In another part of a widening crackdown designed to remove remnants of Bashir’s rule after the recent coup, the transitional military council (TMC) said it will retire all eight senior officers in the National Intelligence and Security Service.

Sudan’s public prosecutor has begun investigating Bashir on charges of money laundering and possession of large sums of foreign currency without legal grounds, a judicial source said earlier on Saturday.

The source said military intelligence officers who searched Bashir’s home found suitcases loaded with more than $US351,000 ($A490,000) and six million euros, as well as five million Sudanese pounds ($A146,000).

“The chief public prosecutor … ordered the (former) president detained and quickly questioned in preparation to put him on trial,” the judicial source told Reuters.

“The public prosecution will question the former president in Kobar prison,” the source said, adding that two of his brothers were also detained on allegations of corruption.

The move comes as leaders of Bashir’s National Congress Party were also placed arrest.

Hassan Bashir, a professor of political science at the University of Neelain, said the measures against Bashir are intended as a message to other figures associated with his rule that they are not above the law.

“The trial is a step that the military council wants to take to satisfy the protesters by presenting al-Bashir for trial,” he said.

Bashir survived several armed rebellions, economic crises, and attempts by the West to turn him into a pariah during his 30-year rule before being toppled by the coup.

At a sit-in outside Sudan’s Ministry of Defence that began on April 6, protesters, who sleep on the pavement, stood besides posters of Bashir that called on the ICC to put him on trial.

-AAP