Special counsel sends wide-ranging request for documents to Justice Department Robert Mueller wants to know more about FBI director's firing.

 -- Special counsel Robert Mueller's team investigating whether President Donald Trump sought to obstruct a federal inquiry into connections between his presidential campaign and Russian operatives has now directed the Justice Department to turn over a broad array of documents, ABC News has learned.

In particular, Mueller's investigators are keen to obtain emails related to the firing of FBI Director James Comey and the earlier decision of Attorney General Jeff Sessions to recuse himself from the entire matter, according to a source who has not seen the request but was told about it.

Issued within the past month, the directive marks the special counsel's first records request to the Justice Department, and it means Mueller is now demanding documents from the department overseeing his investigation.

Sessions and Deputy Attorney General Rod Rosenstein played key roles in Comey's removal. And Sessions has since faced withering criticism from Trump over his recusal and Rosenstein's subsequent appointment of Mueller.

Mueller's investigators now seek not only communications among Justice Department staffers but also any of their communications with White House officials, the source said. Before this request, investigators asked former senior Justice Department officials for information from their time at the department, ABC News was told.

The latest move suggests the special counsel is still digging into, among other matters, whether Trump or any other administration official improperly tried to influence an ongoing investigation.

Last month Sessions told lawmakers he would cooperate with any requests from Mueller and is willing to meet with him.

"I want him to complete his investigation professionally," Sessions told the Senate Judiciary Committee.

Trump, however, has openly expressed disdain for the federal probe, and since his days on the campaign trail, he has questioned the U.S. intelligence community's unanimous conclusion that Russia tried to meddle in last year's presidential election.

Shortly before firing Comey, Trump secretly drafted a memo laying out his reasons for wanting the FBI chief ousted. The New York Times described it as an "angry, meandering" missive.

The draft memo was never publicly released, but a copy was shared with Rosenstein, who had taken command of the Russia-related probe, according to the Times.

To publicly bolster Trump's decision on Comey, the White House released two memos written separately by Sessions and Rosenstein, with both faulting Comey for his handling of the FBI's probe into Hillary Clinton's use of a private email server when she was secretary of state.

During a House hearing in June, Rosenstein refused to say whether he consulted with the White House before Comey's firing or whether anyone asked him to write his memo, insisting such questions "may well be within the scope of the special counsel's investigation."

Rosenstein maintains final supervision over the case, even though he was interviewed by Mueller's team about his role in Comey's firing.

Meanwhile, Trump has taken aim at Sessions for the recusal, launching such biting personal attacks months ago that it appeared that Sessions would not last the summer as attorney general.

At one point, Trump told reporters he wouldn't have nominated Sessions to run the Justice Department had he known Sessions would give up oversight of the investigation.

In July, Trump posted a tweet demanding to know why "our beleaguered" attorney general wasn't "looking into Crooked Hillarys crimes & Russia relations."

In announcing his recusal four months earlier, Sessions said he and "senior career department officials" spent "several weeks" discussing whether his role as top foreign policy adviser to Trump's presidential campaign last year meant his "impartiality might reasonably be questioned."

His work leading the campaign's foreign policy team has left Sessions on the defensive in other ways.

Last week, Senate and House Democrats hammered Sessions for previously telling Congress — under oath — that no Trump campaign associates ever communicated with Russian operatives or intermediaries.

But in the first known charges brought by Mueller, announced last month, former campaign adviser George Papadopoulos admitted he told Sessions and Trump during a meeting last year that he was working with Russians to orchestrate a meeting between Trump and Russian President Vladimir Putin.

Some Democrats accused Sessions of lying to lawmakers, though he has vehemently denied the charge, citing a memory lapse due in part by the "chaos" of the campaign.

During a House hearing Wednesday, Sessions said he now remembers dismissing Papadopoulos' proposal during the meeting last year.

Papadopoulos has pleaded guilty to charges of lying to the FBI about his contacts with Russian nationals.

Former Trump campaign manager Paul Manafort and his former business partner Rick Gates have been indicted on money-laundering and other charges tied to their previous lobbying efforts. They have pleaded not guilty.

Meanwhile, other Trump associates, such as former national security adviser Mike Flynn, are still in Mueller's crosshairs.

Flynn was fired in February after then–acting Attorney General Sally Yates informed White House officials that Flynn lied to them about his contacts with Russian officials.

A spokesman for Mueller declined to comment for this article. A spokeswoman for the Justice Department also declined to comment.