The Washington PostFollowUkraine live briefing: U.S. hunts for source of intelligence leak; Kyiv endures escalating assault on BakhmutStory by Niha Masih, Ellen Francis • 4h ago

As Ukraine mobilizes fighters for a spring counterattack and a commander warns that Russia is reinforcing its Bakhmut front line, leaked U.S. intelligence documents indicate Kyiv is facing a shortfall of Western ammunition and air defense weapons. The United States is searching for the source of the documents that appear to detail classified information about Ukraine, Russia and other nations.Here’s the latest on the war and its ripple effects across the globe.

Key developments

• The Defense Department is still assessing the validity of the leaked documents that have triggered a Justice Department investigation, Pentagon deputy spokeswoman Sabrina Singh said. “An interagency effort has been stood up, focused on assessing the impact these photographed documents could have on U.S. national security and on our Allies and partners,” she said in a statement Sunday.
• One of the leaked documents said a Russian jet nearly shot down a British spy plane near Ukraine last year, an incident that risked embroiling the United States and NATO directly in the war. It was previously disclosed to the British Parliament in the fall by Defense Secretary Ben Wallace, who attributed the missile launch to a “technical malfunction” rather than a near-shootdown.
• The commander of Ukraine’s ground forces said Russia was bringing in special forces and airborne assault units to reinforce its assault on the eastern city of Bakhmut, which has been the focal point of fighting in the Donetsk region for months. In comments to Reuters on Monday, Col. Gen. Oleksandr Syrsky said Russian airstrikes and artillery were destroying buildings and positions, describing the situation as “difficult but controllable.