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Former FBI deputy director Andrew McCabe reportedly kept memos regarding President Donald Trump.

The memos are said to be similar to those kept by former FBI director James Comey about his interactions with Trump.

If McCabe 's memos are anything like Comey's, they would significantly bolster the special counsel Robert Mueller's obstruction-of-justice case against Trump.

Former FBI deputy director Andrew McCabe created memos regarding President Donald Trump, The Associated Press reported Saturday.

A person with direct knowledge of the matter told the AP that the memos are similar to those kept by former FBI director James Comey, which detailed his interactions with the president.

McCabe was fired from the FBI late Friday night, less than 24 hours before he was set to retire with full pension benefits. The firing came amid an internal Department of Justice investigation into his handling of the Hillary Clinton email probe and his role in approving unauthorized disclosures to the media about the inquiry.

Attorney General Jeff Sessions said in a statement Friday that he fired McCabe based on recommendations from the Office of the Inspector General (OIG) and the FBI's Office of Professional Responsibility (OPR). Sessions' decision came despite his statement last year that he would recuse himself from all matters related to the Russia investigation, the Clinton email investigation, and the Clinton Foundation.

McCabe's ouster came after he was the target of a string of public attacks from Trump and his allies, who accused McCabe of putting his thumb on the scale in favor of Clinton.

Meanwhile, McCabe said Friday night that he had been "singled out" because of the events he witnessed in the aftermath of Trump's decision to fire Comey last May.

McCabe is one of three top FBI officials Comey apprised of his conversations with Trump. All three have since been fired, resigned, or reassigned within the bureau.

The White House initially said Comey was fired because of the way he handled the Clinton email investigation. But Trump later said on national television that "this Russia thing" was a factor in his decision. He also reportedly told two top Russian officials that Comey's ouster had taken "great pressure" off of him.

Shortly after the FBI director was terminated, The New York Times reported that Comey created memos documenting conversations with Trump that he believed may have crossed a line.

In one memo, Comey said Trump had asked him to shut down the FBI's investigation into former national security adviser Michael Flynn, who resigned from his position one day before the alleged conversation.

Comey later testified to the Senate Intelligence Committee that Trump also repeatedly asked him for his loyalty and complained about the "cloud" the Russia investigation was casting over his presidency. Comey told lawmakers he saw the comments as an attempt to push him to swiftly end the investigation.

Those interactions — and Comey's subsequent firing — now make up the basis of the special counsel Robert Mueller's investigation into whether Trump sought to obstruct justice in the Russia probe when he dismissed Comey as FBI director last May.

If McCabe had similar interactions with the president about the Russia investigation, it would significantly bolster the obstruction case against Trump.

The AP reported that it's unclear whether McCabe's memos have been turned over to Mueller.