US investigators wiretapped Trump's former campaign chairman Paul Manafort before and after the US presidential election 2016 under secret court orders, sources tell CNN, an extraordinary step involving a high-ranking campaign official now at the centre of the Russia meddling probe.
The government investigation continued into early this year, which included a time period when Manafort was known to have conversations with President Trump, reports CNN.
Some intelligence reports regarding communications raised concerns among investigators that Manafort had encouraged the Russians to help with the campaign, according to three sources familiar with the investigation. Two of these sources, however, cautioned that the evidence is inconclusive.
Special counsel Robert Mueller's team, leading the investigation into Russia's alleged involvement in the election, has been provided details of these communications.
A secret order authorised by the court that handles the Foreign Intelligence Surveillance Act (FISA) began after Manafort became the subject of an FBI investigation that began in 2014. It centred on work done by a group of Washington consulting firms for Ukraine's former ruling party, the sources told CNN.
According to one of the sources, the surveillance was discontinued at some point last year for lack of evidence.
The surveillance was restarted after FBI obtained a new FISA warrant that extended at least into early this year.
Sources say the second warrant was part of the FBI's efforts to investigate ties between Trump campaign associates and suspected Russian operatives. Such warrants require the approval of top Justice Department and FBI officials, and the FBI must provide the court with information showing suspicion that the subject of the warrant may be acting as an agent of a foreign power.
It is unclear when the new warrant started. The FBI interest deepened last fall because of intercepted communications between Manafort and suspected Russian operatives, and among the Russians themselves, that reignited their interest in Manafort, the sources told CNN. As part of the FISA warrant, CNN has learned that earlier this year, the FBI conducted a search of a storage facility belonging to Manafort. It's not known what they found.
The conversations between Manafort and Trump continued after the President took office, long after the FBI investigation into Manafort was publicly known, the sources told CNN. They went on until lawyers for the President and Manafort insisted that they stop, according to the sources.
It is unclear whether Trump himself was picked up on the surveillance.
The White House declined to comment for this story. A spokesperson for Manafort did not comment for this story.
Manafort previously has denied that he ever "knowingly" communicated with Russian intelligence operatives during the election and also has denied participating in any Russian efforts to "undermine the interests of the United States."
The FBI was not listening in June 2016, the sources said, when Donald Trump Jr led a meeting that included Manafort, then campaign chairman, and Jared Kushner, the president's son-in-law, with a Russian lawyer who had promised negative information on Hillary Clinton.
That gap could prove crucial as prosecutors and investigators under Mueller work to determine whether there is evidence of a crime in myriad connections that have come to light between suspected Russian government operatives and associates of Trump.


