A second whistleblower has come forward in the impeachment inquiry against US President Donald Trump.
Mark Zaid, a lawyer for the original whistleblower in the case, said he would be representing a second whistleblower who had direct knowledge of the White House dealings with Ukraine.
He said the person is also an intelligence official.
The impeachment inquiry has centered on Trump's attempts to get Ukrainian president Volodymyr Zelensky to open an investigation into former vice president Joe Biden and his son, Hunter.
Trump and his Republican supporters have dismissed the complaint as politically motivated hearsay.

Hong Kong court finds tycoon Jimmy Lai guilty in landmark security trial
Flash floods kill at least 37 people in Morocco's Safi province
School bus accident in Colombia kills 17, injures 20
Australia plans tougher gun laws after father and son kill 15 at Bondi Beach
Police to release man detained over Brown University mass shooting