Sen. Ben Sasse, R-Neb., called Russian billionaire Oleg Deripaska a “bottom-feeding scum-sucker” during Attorney General William Barr’s hearing before the Senate Judiciary Committee on Wednesday.

The comment came as Sasse focused the discussion on special counsel Robert Mueller’s findings about Russian interference in the 2016 election. The Russian oligarch has been a subject of interest in the Mueller investigation, mainly because of his strong ties to the Russian government and his deep relationship with former Trump campaign chairman Paul Manafort.