Defense Secretary Mark Esper never received a briefing about alleged Russian practices against U.S. troops in Afghanistan that included the term "bounty," he told Congress on Thursday.

Esper said so in an answer to a carefully worded question from Rep. Mike Turner, R-Ohio, who appeared to be aware about how to cue Esper, potentially from his own awareness of the still-secret underlying intelligence about the Russian allegations.

"To the best of my recollection, I have not received a briefing that included the word 'bounty,' " Esper said.

He and Joint Chiefs Chairman Gen. Mark Milley vowed that they are working to ensure American forces in Afghanistan are as well-equipped and well-protected as possible and they suggested the reports about alleged bounties paid by Russian intelligence to Taliban insurgents still aren't confirmed.

Turner also asked Esper whether, if he had been told about "bounties," specifically, he would have taken specific action.

Yes, he said.

"If it was a credible report, a credible, corroborated report, that used those words, certainly it would have been brought to my attention by the by chain of command, by the chairman of the joint chiefs and others, for action. We would have taken upon that action an inter-agency effort to make sure we addressed it," Esper said.

Neither Esper nor Milley appeared to dispute that some underlying activity might be playing out in Afghanistan, but they both presented the situation as one still unresolved or requiring further investigation.

"We're going to get to the bottom of all that," Milley said.

Another Republican, New York Rep. Elise Stefanik, suggested that she and other lawmakers had been briefed about the alleged bounties on Thursday and asked the witnesses to restate their commitment to protecting American forces serving abroad.

"You have a thousand percent commitment," Milley said.

Esper revealed another clue about the origins of the bounty allegations in a separate answer, to a question about whether the Defense Department itself was responsible for assessing that bounties have been paid to Afghan insurgents.

The defense secretary said this: "It was not produced by a DOD intelligence agency" — which rules out a number of big organizations, including the intelligence components of the military services, the Defense Intelligence Agency and perhaps the National Security Agency, which belongs organizationally to the Pentagon.

Esper said he'd first learned about the allegations in February in an "intelligence piece of paper" — perhaps a reference to a reported classified CIA bulletin that has been described by The New York Times.

Republicans on the House Armed Services Committee sought to defend President Trump on Thursday and puncture the criticism that his administration bungled the discovery of the alleged bounty practices.

In their telling, officials continue to assess unreliable reports and that's why the matter was never singled out for the president in an in-person presentation.

Trump has called the alleged bounty practices a "hoax" and the White House hasn't said it'll take any action against Russia in retaliation for whatever is taking place on the ground in Afghanistan.

The underlying intelligence has not become public.

A number of press reports, however, including those led by The New York Times, have described a broad range of evidence, including electronic wire transfers and personal comments by Taliban insurgents, confirming that Russia offered monetary incentives to insurgents for targeting Western troops.

Critics have faulted Trump for creating a process inside his administration in which he reportedly isn't given pertinent intelligence because it might upset him or in which aides effectively bury unpleasant material in written documents that Trump doesn't read.

Rep. Seth Moulton, D-Mass., said the presence or absence of a specific term in official briefing materials "proves nothing — what matters is the substance."

Also on Thursday, Sen. Tammy Duckworth, D-Ill., asked Esper in a letter whether the Defense Department is investigating whether any American deaths in Afghanistan may have been linked with the alleged Russian bounty practices.

Her letter alluded to the families of such fallen troops, often denoted with a gold star, and the Russian military intelligence agency that has been connected with the practice, the GRU.

"It is unacceptable that to date, the Trump administration appears to be ignoring a matter of great importance to Gold Star family members whose loved ones were killed while serving in Afghanistan: were any U.S. troop casualties in Afghanistan connected with the alleged GRU bounty payments to Taliban-linked militants?" Duckworth asked. "Gold Star families deserve an answer to this question."

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