A concentrated, nine-minute-long Russian drone attack on Ukraine's second-largest city of Kharkiv on Wednesday killed six people and injured 64, including nine children, Ukrainian officials said.The attack followed Russia's two biggest air assaults of the war on Ukraine this week,

The attack used almost 500 drones and missiles, breaking a record set just days earlier, as Russia tries to overwhelm Ukraine’s air defenses, which shot down most of the weapons.

One of the hardest-hit areas was the city of Kharkiv in northeastern Ukraine, where 17 attack drones struck two residential districts, Mayor Ihor Terekhov said. Emergency crews, municipal workers and volunteers worked through the night to extinguish fires, rescue residents from burning homes, and restore gas, electricity and water services.