By CHAD DAY and ERIC TUCKER
Associated Press

WASHINGTON (AP) - Special counsel Robert Mueller has brought additional charges against President Donald Trump's campaign chairman and a longtime associate who prosecutors have said has ties to Russian intelligence.

The new indictment was unsealed Friday against Paul Manafort and Konstantin Kilimnik just days after prosecutors accused the two men of attempting to tamper with witnesses as Manafort awaits trial of felony charges related to his work on behalf of Ukrainian interests.

The latest charges increase Manafort's legal jeopardy if he continues an aggressive battle with prosecutors, and could be an effort by Mueller to induce a guilty plea and secure the testimony of a critical campaign adviser to Trump. They also come as Trump and his attorney, Rudy Giuliani, have heaped public criticism on the Mueller investigation in an attempt to undermine it.

The charges against Manafort do not relate to his work on the Trump campaign or involve allegations of Russian election interference, a fact that the president has routinely noted as he tried to distance himself from his former top campaign adviser.

The new indictment charges Manafort and Kilimnik with obstruction of justice and conspiracy to obstruct justice related to contacts they had with two witnesses earlier this year. The witnesses, who had worked with Manafort as he represented a pro-Russian political party in Ukraine, have told the FBI that they believed Manafort and Kilimnik were trying to get them to lie about the nature of their work.

The charges mark the second time since October that an indictment against Manafort has been amended to include additional allegations.

Through a spokesman, Manafort, 69, has maintained his innocence. The spokesman, Jason Maloni, said Friday that Manafort and his attorneys were reviewing the new charges.

Kilimnik, 48, has previously declined to comment on the allegations. He also has denied being connected to Russian intelligence agencies.

Prosecutors say the contacts via phone and encrypted messaging applications first occurred in February, shortly after a grand jury returned a new indictment against Manafort and while he was confined to his home. Kilimnik also reached out to witnesses in April.

Manafort is awaiting trial in federal court in Washington and Alexandria, Virginia. His co-defendant, Rick Gates, pleaded guilty in February and agreed to cooperate with prosecutors.

The allegations of witness tampering relate to Manafort's criminal case in Washington where he faces charges of money-laundering conspiracy, false statements and acting as an unregistered foreign agent for Ukrainian interests. In Virginia, he also faces bank fraud and tax evasion charges.

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