Reuters reported the information.Russia's Syzran oil refinery ceased processing operations on December 5 after sustaining damage from a Ukrainian drone strike, according to two industry sources who spoke Tuesday. The attack targeted the facility's CDU-6 crude distillation unit, a critical piece of primary equipment that processes raw crude oil into usable petroleum products.The Ukrainian military announced Friday that it had conducted long-range strikes on the Syzran refinery and the Temryuk port in Russia's Krasnodar region overnight. The strikes represent a continuation of reciprocal attacks on energy facilities by both nations as diplomatic efforts to end the war remain stalled.This marks the second time this year that the CDU-6 unit has been struck by drones. The facility previously sustained damage in August, requiring approximately two weeks of repairs. However, one source indicated the latest repairs could take significantly longer—potentially lasting about a month.The refinery's owner, Rosneft, has not responded to requests for comment on the incident or the expected timeline for resuming operations.The Syzran plant operated well below its full capacity last year, processing approximately 90,000 barrels per day, or 4.3 million metric tons annually, according to industry sources. In 2023, the facility produced 800,000 tons of gasoline, 1.5 million tons of diesel, and 700,000 tons of fuel oil.The ongoing attacks on energy infrastructure by both Ukraine and Russia have intensified as peace negotiations have failed to gain traction, with both sides viewing these facilities as strategic targets in the war.