McCabe's interview with Mueller's prosecutors apparently included what he knows about former FBI director James Comey's firing.

The bottom line: The memos include corroboration by McCabe of Comey's account of his own firing by Trump, according to the source.

McCabe alluded to that in a 10-paragraph statement right after his firing, in which he said: "[M]y testimony to the House Intelligence Committee revealed that I would corroborate former Director Comey's accounts of his discussions with the President."