Rep. Brad Sherman (CA-30) has officially filed an article of impeachment against Donald Trump with the U.S. House of Representatives. From The Hill:

Rep. Brad Sherman (D-Calif.) formally introduced an article of impeachment against President Trump on Wednesday that accuses the president of obstructing justice during the federal investigation of Russia’s 2016 election interference.

Rep. Sherman says the president’s decision to fire FBI Director James Comey was a key factor in his decision to file:

Sherman argues that Trump’s abrupt firing of James Comey as FBI director in May amounts to obstructing justice and "high crimes and misdemeanors" amid the probes of whether Trump's campaign colluded with the Russian government to swing the election.
He cites Comey’s allegations that Trump pressured him to drop the FBI’s investigation into ousted former White House national security adviser Michael Flynn, as well as Trump’s shifting story on why he fired Comey.

Of course the Republicans have a massive advantage in the House, which would require a majority to move forward with impeachment. That, however, could change in 482 days, when U.S. voters will have a chance to hand the majority in Congress back to Democratic leadership. If that happens? Oh, Lordy, Trump will be in trouble.