Story highlights Trump fired Comey last week

Conversations Comey had with Trump were documented by the former FBI director

Washington (CNN) Former FBI Director James Comey wrote in a memo that President Donald Trump asked him to end the investigation of national security adviser Michael Flynn, according to a source familiar with the matter.

Comey was so appalled by the request that he wanted to document it, the source said. Comey shared it with FBI senior officials, according to the source.

Why did he do it?

Comey would write down everything that happened -- the good and the bad.

"Everything he could remember," the source said.

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