A federal grand jury in Washington, DC, on Friday filed the first charges in connection with the investigation into the alleged Russian meddling in the 2016 United States presidential election, CNN reported quoting unidentified officials.

The investigation is led by US special counsel Robert Mueller, a former director of the Federal Bureau of Investigation.

Anyone who is charged can be taken into custody as soon as Monday, CNN reported. However, it is still unclear what the charges are.

Mueller has been investigating financial dealings between Trump aides and foreign governments, including Russia and Turkey, for possible money laundering, and tax evasion, Reuters reported quoting unidentified officials.

Deputy Attorney General Rod J Rosenstein had appointed Mueller special counsel in May, shortly after US President Donald Trump fired FBI Director James Comey. Comey had been leading an investigation into the president’s campaign ties with Russia.

With an unblemished reputation, Mueller is considered one of the most credible law enforcement officials in the US. Thus, his appointment was praised by both Democrats and Republicans. Lashing out at Mueller in June, Trump had confirmed that he was being investigated in the case. Trump had called it a “witch hunt” against him.

As a special counsel, Mueller is answerable to the deputy attorney general as well as Trump, but he will have more autonomy to run an investigation than a US attorney. He is free to choose whether to consult with or inform the US Justice Department about his inquiry. He is also authorised to investigate any links whatsoever and may file criminal charges.

Besides Russian interference in the election, Mueller’s investigation also focuses on any obstruction of justice on the part of the president, who may have tried to hinder the probe.