UNITED NEWS INTERNATIONAL (UNI) — Special counsel Robert Mueller has accused President Trump’s former campaign chairman Paul Manafort of attempting to tamper with a witness in his ongoing criminal cases.

Mueller, who is investigating possible collusion between the Trump campaign and Russia, asked a judge on June 4 to send Manafort to jail as he awaits his trial.

Manafort was arraigned in October and is currently out on house arrest and a $10 million bail.

Mueller’s office said in the new court filing that while under house arrest, Manafort “repeatedly” contacted two witnesses in an effort to influence their testimony.

He has pleaded not guilty to a number of charges related to his failure to disclose his lobbying work for a foreign government, including conspiracy against the United States, tax fraud and money laundering.