The Turkish offensive against Kurds in northern Syria is “on the cusp of genocide,” Sen. Richard Blumenthal, D-Conn., said Friday as fighting continued despite a Trump administration's announcement of a five-day cease-fire.

The Senate Armed Services Committee, on which Blumenthal serves, received a classified briefing Thursday on Turkey’s incursion from Defense Secretary Mark Esper and Army Gen. Mark Milley, the chairman of the Joint Chiefs of Staff.

Blumenthal said he could not reveal the details of the military presentation but described the mood in the room as serious and solemn.

“There was no happy talk,” he said. “My reaction was horror and shame. And the American people should at least hear the essential facts of what is happening there.”

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Esper said discussions with members of the House and Senate Armed Services committees were "serious, candid, and constructive."

He said he had spoken with Turkey's minister of defense Friday.

"I reiterated the United States' position that Turkey must adhere to the full terms of this agreement, and that we expect Turkey to ensure the safety and well-being of all people in the area controlled by Turkish Forces," Esper said. "Protecting religious and ethnic minorities in the region continues to be a focus for the Administration."

Turkey invaded northern Syria soon after Trump ordered the withdrawal of U.S. forces from the region, unleashing a free-for-all as Russia, Iran and other powers vie for influence.

Thursday, the Trump administration announced that Turkey had agreed to halt its assault in Syria for five days. That happened after Vice President Mike Pence and Secretary of State Mike Pompeo visited Turkey.

Turkey's government described the agreement as a "pause." Critics said the deal left many questions unanswered – including the fate of the Kurds – and was too little, too late.

A U.S. official who is not authorized to speak publicly agreed with Bluementhal’s characterization of “horror and shame.”

The official said the cease-fire is not holding, and predicted it would cause more confusion and deaths among the Kurds.

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Since 2014, a U.S.-led coalition, which has relied heavily on Kurdish ground forces, has rolled back the gains made by ISIS militants in Iraq and Syria.

Turkey regards the Kurdish fighters as terrorists and warned Trump that it planned an offensive against them. That occurred shortly after Trump announced the departure of U.S. troops.

The withdrawal of U.S. troops from Syria will leave the Kurds at the mercy of Turkey, Blumenthal said. It will also eliminate sources of intelligence.

"Once we withdraw our personnel and we lose credibility of the Kurds, our visibility on what is happening there is very substantially diminished," he said. "Our human intelligence evaporates. We'll have very limited sources of intelligence."

Turkish President Recep Tayyip Erdogan disputed Friday that his forces were not abiding by the pause.

"I don’t know where you’re getting your news from. According to the news I received from my defense minister, there is no question of clashes. These are all speculation, disinformation," he told reporters in Istanbul Friday, according to Turkey's official Anadolu news agency.

Erdogan also said he wouldn't forget a letter sent to him by Trump, which he described as lacking "political and diplomatic courtesy."

In the letter, Trump urged his Turkish counterpart not to be a "tough guy" over Syria. Erdogan received it before he launched an incursion across the border into Syria. A BBC report claimed Erdogan angrily threw the letter in the trash after reading it.

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