A second intelligence official with concerns and more direct knowledge regarding President Donald Trump’s dealings with Ukraine is considering filing a whistleblower complaint, The New York Times reported Friday.

The Times’ report, citing two people briefed on the matter, comes as House Democrats ratchet up their impeachment inquiry centered on Trump’s July phone call with Ukrainian President Volodymyr Zelensky by issuing a subpoena to the White House and a documents request to Vice President Mike Pence.