For 1,5 years Robert Mueller has been investigating the supposed collusion between Trump and the Russians. Nothing has been found so far. So, they arrest people, they try to make them speak; then they set them free and continue trying to make them speak.
Recurrent pro-Kremlin narrative on special counsel Robert Mueller's Russia probe. Read more here.
By January 25, 2019, during the investigation of 'the 2016 US-election interference by Russia and related matters' (also known as special counsel Robert Mueller's Russia probe) eight people have pleaded guilty or been convicted.
Another 27 individuals, including 12 Russian intelligence officers, have been indicted, along with three Russian companies. The majority of indictments are "conspiracy against the US" and "obstruction of justice". They concern the hacked and stolen e-mails of the Democratic National Committee, which were released by Wikileaks. Also, the massive creation of false social media profiles by the Russian "Agency of Internet researches" allowed to indict Russian citizens behind the accounts. See more: Mueller's indictments: Who is Who (Wall Street Journal).