NPR has reported that Attorney General Eric Holder is leaving the Obama administration after nearly six years of service; Holder will reportedly announce his resignation later Thursday. His exit from the Obama administration won't be quick, though — Holder plans to wait until his successor is confirmed, a process that can take months.

A former U.S. government official told NPR that Holder has been "adamant" about wanting to resign from his post. According to The New York Times, Holder discussed his resignation with President Obama over Labor Day weekend.

The 63-year-old is the fourth-longest-serving attorney general in the history of the position, and is one of the most senior staff members of Obama's Cabinet. Holder is also the first African-American to serve as attorney general, and his determination to fight racial injustices in America has made him a polarizing figure since he assumed the position in 2009.

It's a strange time for Holder to leave the administration, considering the Justice Department is still knee-deep in its investigation of the shooting of 18-year-old Michael Brown on Aug. 9 in Ferguson, Missouri, as well as a separate civil rights investigation of the Ferguson Police Department. In August, Holder heeded calls to make good on his promise to focus on civil rights issues, making an unprecedented trip to Ferguson to meet with local residents, law enforcement officials, and Brown's family.

Earlier this week, Holder called Ferguson a "moment of decision" while delivering a speech at New York University's Brennan Center for Justice:

These tensions simmer every day in far too many communities across the country. The situation in Ferguson has presented leaders across the nation … with a moment of decision, a moment of decision, a series of important questions that can no longer be avoided.
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According to NPR, Holder's decision to leave is entirely his own. Sources close to the situation told the news source that the Obama administration would have been happy to have Holder serve for the full eight years.

So, who will be replacing Holder? Early reports point Solicitor General Don Verrilli, who previously served as deputy counsel to Obama, as well as associate deputy attorney general in the Justice Department. Verrilli was appointed to the solicit general position in 2011 by Obama, replacing Elena Kagan, who left for the Supreme Court.

Considering Verrilli's close relationship with the Obama administration, his nomination wouldn't be such a surprise. Sources say his legal skills are already valued by the administration, who view him as one of their top go-to legal counsel.

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