The judge declared a mistrial on 10 other charges after jurors failed to reach a unanimous verdict.
Donald Trump's former campaign chairman Paul Manafort has been found guilty of tax fraud.
He was found guilty of eight out of 18 charges relating to financial crime.
The judge declared a mistrial on the 10 other charges after jurors failed to reach a unanimous verdict.
The jury deliberated for four days before announcing the verdict at the federal courthouse in Alexandria, Virginia.
Prosecutors spent more than two weeks presenting their case as they sought to prove Manafort concealed millions of dollars in offshore accounts from the IRS.
It is the first trial victory for special counsel Robert Mueller's team.
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The judge declared the court is in recess following the verdicts.