A demolition worker has been killed when a sports complex roof collapsed prematurely in the Russian city of St Petersburg, officials say.

Drone footage shows the man with a blow torch cutting through metal supports at the SKK Peterburgskiy when the massive structure disintegrates.

He is seen trying to scramble to the safety of a cage suspended from a crane.

The body of a 29-year-old man was found later in the rubble.

Filmed by a local news agency