Ukrainian officials say three people were killed and 13 were wounded when Russia attacked the country with waves of drones and missiles.

A concentrated, nine-minute-long Russian drone attack on Ukraine's second largest city of Kharkiv in the middle of the night killed at least two people and injured 57, including seven children, regional officials said on Wednesday.

Drones are “ubiquitous, because they are quite useful, and they're demonstrating that every day in Ukraine,” one analyst told NBC News.