(Reuters) -Officials in Kharkiv, Ukraine's second-largest city, said on Tuesday that drones hit populated areas of the city and one drone destroyed two floors of a college dormitory.

The chief of police in Kharkiv region in northeastern Ukraine, Volodymyr Tymoshko, said there were two night-time strikes -- one on the college and one on the city centre.

"One of the drones destroyed two floors of a dormitory," mayor Ihor Terekhov wrote on the Telegram messaging app. "A fire broke out and emergency services are attending," he added.

"Very difficult night in Kharkiv. Indeed, there were three hits," he told Ukrainian television, adding that the dormitory was not being used.

Regional governor Oleh Synehubov said a sports complex in the city's Shevchenkivskyi district was hit, damaging a two-storey building. A 63-year-old security guard had been injured and was in hospital.

President Volodymyr Zelenskiy said on Telegram that Russia attacked the city with five Shahed drones.

A video posted on social media showed the top of a building ablaze and smoke billowing upwards.

Reuters could not immediately confirm the attack or determine the location of the site in the video.

(Reporting by Ron Popeski and Oleskandr Kozhukhar; additional reporting by Anna Pruchnicka; Editing by Leslie Adler and Ed Osmond)