Rep. Keith Ellison wants the Pentagon to disclose any information it has about white supremacists currently serving in the the military.

The Minnesota Democrat sent a letter to Defense Secretary James Mattis last week asking about “steps currently being taken to screen recruits for extremist ties,” Military Times reported.

Ellison’s letter came after a ProPublica and “Frontline” report found that three active duty service members were associated with Atomawaffen, a white supremacist group that has been tied to five murders in the past year.

“The involvement of service members in white supremacist organizations or other hate groups is cause for significant concern, particularly given their combat and weapons training,” Ellison wrote in his letter.

Ellison also pointed to a Military Times survey that found that nearly 25 percent of respondents said they had seen “examples of white nationalism from their fellow service members.”

Similarly, the survey said that 42 percent of non-white troops had personally experienced white nationalism in the military.

Ellison’s letter requested that Mattis produce information on the number of reports of service members with extremist ties for the past five years.

“In addition, I seek information on the steps currently being taken to screen recruits for extremist ties,” he said.

The ProPublica and “Frontline” report highlighted that one member of the Marines was allegedly involved in the racial violence around white nationalist demonstrations in Charlottesville, Virginia, last year.

Since then, Mattis has praised the military’s “widely diverse force.”

Ellison requested that Mattis send the response by May 21.

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