The FBI is probing new emails related to Hillary Clinton, FBI Director James Comey said in a Friday letter.
"In previous congressional testimony, I referred to the fact that the Federal Bureau of Investigation (FBI) had completed its investigation of former Secretary Clinton's personal email server. Due to recent developments, I am writing to supplement my previous testimony," Comey wrote.
"In connection with an unrelated case, the FBI has learned of the existence of emails that appear to be pertinent to the investigation. I am writing to inform you that the investigative team briefed me on this yesterday, and I agreed that the FBI should take appropriate investigative steps designed to allow investigators to review these emails to determine whether they contain classified information, as well as to assess their importance to our investigation," he added.
"Although the FBI cannot yet assess whether or not this material may be signifcant, and I cannot predict how long it will take us to complete this additional work, I believe it is important to update your Committees about our efforts in light of my previous testimony," Comey concluded.
Stocks turned negative after the report of the new probe. Many analysts have said that markets were pricing in a Clinton victory in November.
The letter was addressed to several lawmakers who chaired committees relevant to the FBI investigation into Clinton's use of a private email server.
NBC News reported that Judiciary Committee Republicans were not expecting this news from the FBI, and it is not in response to any question from the Senate Judiciary Republicans.
"We're interested to know what else they're going to be looking at," a spokesman for the Judiciary Committee Republicans said.
This story is developing. Please check back for further updates.