In a big Washington shakeup, President Trump fired FBI Director James Comey on Tuesday.
In a statement, Trump said the ousting will "mark a new beginning" for the FBI.
This comes after Comey misspoke during last week's congressional hearing investigating Hillary Clinton's use of a private email server.
Comey testified Clinton's top aide Huma Abedin forwarded "hundreds of thousands of emails" to the laptop of her husband, Anthony Weiner. But the FBI sent a letter to Congress saying Abedin only forwarded a small number of emails.
Comey re-opened the email server probe just over a week before Election Day, and Clinton was cleared of any wrongdoing a few days later.
Some Democrats, including Clinton, say Comey helped sway the election in Trump's favor.
The White House says its search for a new director will start immediately.
Senate Minority Leader Charles Schumer says he told the president he was making a big mistake.
He calls it a troubling pattern in the Trump administration and is calling on the deputy attorney general to appoint a special prosecutor.
Schumer says the investigation must be run as far away as possible from the White House and anyone Trump has appointed.
"Given the way the president fired Director Comey, any person who he appoints to lead the Russia investigation will be concerned that he or she will meet the same fate as Director Comey if they run afoul of the administration," Schumer said.
Schumer says if Deputy Attorney General Rod Rosenstein does not appoint an independent special prosecutor, every American will rightly suspect that firing Comey was part of a cover-up.