FBI Director James Comey's unexpected firing on Tuesday came just as his bureau was stepping up its investigation into possible ties between President Donald Trump's campaign team and Russians attempting to influence the election, The Wall Street Journal reports.

Comey recently began getting daily instead of weekly reports on the probe, according to the Journal, with the focus appearing to be on companies that have done business with Trump or that have some connection to him.

That might include businesses associated with Trump's son-in-law, Jared Kushner, who is also a top White House aide, the paper quoted one source.

Comey had requested more funding for the probe last week, and on Monday — one day before his dismissal — he had briefed lawmakers on Capitol Hill about his request for additional resources. Lawmakers reportedly asked Comey if he could speed up his investigation.

Senate Intelligence Committee investigators have gotten more concerned as they saw intelligence reports, the Journal reports, though some GOP lawmakers say they have not seen anything to worry them that anything improper has taken place between Trump's team and Russia.

"We are confident that when these inquiries are complete, there will be no evidence to support any collusion between the campaign and Russia," a White House spokesman said, and Deputy White House Press Secretary Sarah Huckabee Sanders told reporters the FBI probe will continue.