Southern Poverty Law Center President Richard Cohen stepped down Friday, creating a widening crack in the leadership of a nonprofit mired in recent controversy.

Cohen’s resignation comes a little more than a week after he fired the center’s co-founder and chief litigator, Morris Dees, for unspecified misconduct. In a March 14 statement, Cohen underscored the importance of “ensuring the conduct of our staff reflects the mission of the organization and the values we hope to instill in the world.”

“When one of our own fails to meet those standards, no matter his or her role in the organization, we take it seriously and must take appropriate action,” Cohen wrote. The statement did not offer specifics on the circumstances behind Dees’s termination, and the center declined to provide additional details.

Dees told the Associated Press his firing involved a “personnel issue,” but declined to offer more information.

“I think the Southern Poverty Law Center is a very fine group and I devoted nearly 50 years of my life to it and I’m proud of its work,” Dees told the AP. “About being fired, all I can say is it wasn’t my decision and I wish the center the best.”

In an email obtained by The Washington Post, Cohen announced his resignation to staff and wrote “Whatever problems exist at the SPLC happened on my watch, so I take responsibility for them.”

“And I hope that everyone will let the process play out before jumping to conclusions,” he continued. “We can’t be calling for a review and simultaneously casting blame before that review is complete.”

The Washington Post also received confirmation Rhonda Brownstein, the SPLC’s legal director and a member of its senior leadership staff, also resigned on Thursday.

In the wake of Dees’ departure, attorney Tina Tchen, previously chief of staff to former First Lady Michelle Obama, was hired to conduct a “top-to-bottom” review of the SPLC, the organization said last week, in an effort to assess internal climate and workplace practices and ensure the environment is “one in which all voices are heard and all staff members are respected.”

An SPLC spokesman told The Post that Cohen’s departure will provide room for Tchen to conduct a review of the organization’s policies, operations and procedures and implement her recommendations. The center’s board will meet in the coming days to identify its new president, and an interim successor will lead the organization until then, according to Cohen’s email to staff.

“Every workplace, including social justice organizations, must work hard to create a workplace culture that fully reflects their values and priorities, including when it comes to racial and gender diversity,” Tchen said upon being hired.