Special counsel Robert Mueller has added a prosecutor who specializes in cybercrimes to his team investigating Russia’s interference in the election and possible collusion with the Trump campaign.

A spokesman for Mueller’s office told The Hill on Wednesday that Ryan Dickey was added to the counsel’s high-power team of prosecutors in November after serving with the Justice Department’s Computer Crime and Intellectual Property Section.

Dickey, the website reported, is the first veteran prosecutor of cybercrimes to join the probe.

Cybercrimes play a large role in the investigation, as Russian hackers stand accused of stealing emails from Hillary Clinton’s campaign and the Democratic Party.

President Trump has repeatedly attacked the probe, and has falsely asserted that it has been proven that there was no collusion between Team Trump and Vladimir Putin’s Russia, including in a tweet Wednesday.

“The single greatest Witch Hunt in American history continues. There was no collusion, everybody including the Dems knows there was no collusion, & yet on and on it goes. Russia & the world is laughing at the stupidity they are witnessing. Republicans should finally take control!” the commander-in-chief wrote.