Former Trump campaign manager Paul Manafort is being held in solitary confinement after his bail was revoked for witness tampering last week.

"Paul is in solitary confinement for his own safety from the general prison population," former Trump lawyer John Down told Fox News on Tuesday. "The warden is concerned that someone would violently attack Paul just for street cred."

"They make all prisoners return to their cells whenever Paul needs to leave his cell," Dowd continued.

It is unclear where Manafort is being held at this time.

Manafort appeared before U.S. District Judge Amy Berman Jackson in Washington last week after special counsel Robert Mueller accused him of attempted witness tampering ahead of his trial before a federal court.

Previously, Jackson set Manafort's bail for $10 million, and placed him on house arrest. The special counsel's office requested last week to have Manafort's house arrest conditions "revoked or revised." Manafort has also pleaded not guilty to bank and tax fraud in Virginia.

Manafort's trial in D.C. is scheduled to start on Sept. 7, while his Virginia case will begin July 10.