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The classified Senate briefing on the strike that killed Qasem Soleimani became tense and heated amid repeated questions from Democratic senators about the intelligence regarding how imminent a future attack would be, according to four senators who were in the room.

Administration representatives ended up leaving before all questions were asked and departed after the allotted time of 90 minutes, two senators said.

Democrats pressed for specifics of the targets and timeline, and while senators said the timeline was described as within “days,” the information provided in today’s briefing did not explicitly back that up, according to Democrats.

At one point, Democratic Sen. Amy Klobuchar pressed on the imminence of the attack, and several senators said they came away with the sense her specific question remained unanswered. Administration officials were pressed about whether the attacks would be carried out especially since Iran's supreme leader apparently had not signed off on what Soleimani was plotting, sources said.

Republicans expressed frustration over the Democratic posture during the briefing, with GOP Sen. Lindsey Graham saying they were “out of their minds” for how they approached the strikes.

Sen. Chuck Schumer, a Democrat from New York, spoke to reporters following the briefing. Here's what he said about it: