Officials familiar with Comey’s thinking said the director on Thursday faced a quandary over how to proceed once the emails, which number more than 1,000 and may duplicate some of those already reviewed, were brought to his attention.

Comey had just been briefed by a team of investigators who were seeking access to the emails. The director knew he had to move quickly because the information could leak out…

An official familiar with Comey’s thinking said that “he felt he had no choice.”

“What would it look like if the FBI inadvertently came across additional emails that appear to be relevant to the Clinton investigation and not at least inform the Oversight Committee that this occurred?” the official said. “What would be the criticism then? That the FBI hid it? That the FBI purposely kept this information to themselves?”