Which political figures are being investigated over Russian interference in US elections?

A day after news broke that special counsel Robert Mueller’s investigation into Russian interference with the 2016 US presidential election is focusing on former President Donald Trump’s former campaign chairman Paul Manafort and two other figures close to him, the House Intelligence Committee has voted to appoint a special counsel.

The House Intelligence committee on Thursday approved a subpoena to Special Counsel Robert Mueller seeking information about the Russian involvement in the 2016 presidential election.

The move is expected to further heighten tensions between Congress and the special counsel, who is leading the probe into whether the Trump campaign colluded with the Russian government to influence the outcome of the election.

In the past week, Trump has lashed out at Mueller, calling him a “nasty man” and a “liar” and warning that if the special prosecutor finds “any evidence of collusion” with Russia, he will “let it be known to the American people”.

The House panel approved the subpoena after a bipartisan group of lawmakers raised concerns over the probe, and urged it to release more documents.

The committee, which is also investigating Russia’s interference in the election and possible collusion by Trump associates, has already subpoenaed several Trump campaign aides, including Manafort and Jared Kushner.

“The committee has determined that these witnesses are credible and have not waived their right to remain silent,” committee Chairman Devin Nunes, a Republican, said in a statement.

The subpoena is a response to an earlier request from the committee, made to the FBI, which has been investigating Russian interference and possible coordination with Trump associates.

The FBI and Justice Department declined to comment on the subpoenas.

Manafort has not been a subject of Mueller’s probe, which was launched after his lobbying firm was paid nearly $16m in 2016 by a Russian oligarch who had ties to Moscow’s ruling family.

The Trump administration has vigorously denied any collusion between the Trump camp and Russia.

Mueller’s office has said the investigation is “in full swing” and is “unprecedented” and has interviewed witnesses from all over the country.