« GOP pushes for one-week funding bill to avert government shutdown | Main | Nearly half of Americans think there's a 'deep state' in US: Poll »

Former Trump adviser Mike Flynn under DoD investigation

Jabin Botsford/The Washington Post via Getty Images(WASHINGTON) -- Retired Lt. Gen. Michael Flynn was personally warned by the Pentagon against receiving payments from foreign governments in 2014 after leaving the Defense Intelligence Agency, Rep. Elijah Cummings, D-Md., revealed Thursday.

The top Democrat on the House Oversight Committee released three new documents on Flynn, included a letter from the DIA counsel’s office in response to an inquiry from Flynn in October of 2014.

The letter, a primer on ethics restrictions that apply to retired military officers, warned that Flynn was prohibited from receiving foreign payments without prior approval under the Emoluments Clause of the U.S. Constitution.

"The Pentagon's warning to Gen Flynn was bold, italicized and could not have been clearer," Cummings said in a news conference Thursday.

Flynn, who was President Trump’s first national security adviser, was fired after he misled Vice President Mike Pence about conversations he had with a Russian official.

Cummings also revealed Thursday that the Defense Department inspector general has opened an investigation into Flynn and whether he sought permission to receive foreign payments, including payments in exchange for an appearance in Russia.

Another document, an unclassified letter from the Defense Intelligence Agency, indicates that the Defense Intelligence Agency "did not locate any records" relating to Flynn receiving foreign payments, or any records that he sought permission to do so.

“These documents raise grave questions about why General Flynn concealed the payments he received from foreign sources after he was warned explicitly by the Pentagon,” Cummings said in a statement.

Cummings called on the White House to provide documents on Flynn requested by the House Oversight Committee as part of its investigation into the former national security advisor.

“There’s obviously a paper trail,” he said.

A Pentagon spokesman confirmed that on April 4 the Defense Department’s Inspector General began an investigation into Flynn’s alleged violations of the Emoluments Clause.

ABC News has reached out to Flynn's lawyer for comment.

Copyright © 2017, ABC Radio. All rights reserved.

ABC News Radio