Former Trump campaign director Paul Manafort turned himself over to the FBI Monday morning.

Manafort walked into the FBI’s field office in Washington, D.C., Monday at approximately 8:15 a.m., after he and his business associate, Rick Gates, were instructed to turn themselves in to federal authorities. Manafort and Gates are the first to be charged in special counsel Robert Mueller’s ongoing investigation into President Donald Trump’s campaign ties to Russia.

Former Trump campaign chairman Paul Manafort arrives at FBI in Washington, D.C. to be processed https://t.co/lFkUJjRmIL video via @DelWilber pic.twitter.com/EFh4U90gJO

— Capital Journal (@WSJPolitics) October 30, 2017

The former Trump campaign director was already under investigation for violating federal tax law and whether or not he properly reported foreign lobbying money.

The charges against Manafort and Gates are not clear at this time, The New York Times reports. Gates is a longtime associate of Manafort and serves as his junior partner at his firm. Gates became a point of interest in the investigation into Mueller after investigators found Gates name on documents linking Manafort’s firm to offshore companies that received payments from Eastern European politicians and businessmen.

Manafort’s indictment comes after a federal grand jury approved the first criminal charges Saturday in Mueller’s investigation.

The former Trump campaign director was already under investigation for violating federal tax law and whether or not he properly reported foreign lobbying money. F.B.I. agents raided Manafort’s Florida home in the summer, and warned him of a pending indictment.

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