The arrests came as authorities said they had searched Bashir's home and found suitcases loaded with more than $351,000 and six million euros, as well as five million Sudanese pounds.
Sudan’s attorney general also ordered the formation of a committee to oversee investigations into crimes involving public funds, corruption and criminal cases related to recent events.
The crackdown, observers say, is intended to placate protesters who want the military council which took over after toppling Bashir to hand power to civilians, Presstv reported.
The new moves were taken on the eve of protest leaders' planned announcement of a ruling civilian council they say will replace the country's current ruling military body.
On Saturday, military rulers and protest leaders held a round of negotiations as thousands of demonstrators massed outside the army headquarters, calling for a civilian rule.
"We clarified our main demand, which is the transfer of power to civilian authorities," Siddiq Yousef, a senior member of the umbrella group leading the protest movement, told state television.
"We agreed to continue negotiations to reach a solution that satisfies both the sides, so that the transfer of power will happen in a peaceful way," he said.
He did not say whether protest leaders will go ahead with their planned unveiling of a ruling civilian council on Sunday.
Since Bashir's ouster on April 11, Sudan has been ruled by a 10-member military council which has so far resisted calls to transfer power to a civilian body.
The foot-dragging has prompted thousands of protesters to remain camped outside the army headquarters in central Khartoum, calling on the military rulers to step down.
Protest leader Ahmed al-Rabia said he expected mounting pressure from the street and from the international community to make the military council cede power in "two to three weeks".
"We are done with the easy part (toppling Bashir). We want to remove the entire regime," said Rabia.
In order to appease the protesters, the military council has agreed to demands such as detaining Bashir and releasing many political detainees and protesters.
On Saturday, authorities arrested Ahmed Haroun, the acting head of Bashir's party, former first vice president Ali Osman Taha, former Bashir aide Awad al-Jaz, the secretary general of the Islamic movement Al-Zubair Ahmed Hassan and former parliament speaker Ahmed Ibrahim al-Taher.
Parliament speaker Ibrahim Ahmed Omar and presidential aide Nafie Ali Nafie were also put under house arrest.
The military council further said it will retire all eight of the officers ranked lieutenant general in the National Intelligence and Security Service.
A judicial source also said Sudan's public prosecutor had begun investigating Bashir on charges of money laundering and possession of large sums of foreign currency without legal grounds.
However, the measures are unlikely to pacify the protesters and the push for power transition is expected to continue.