Explosion rocks Russian military academy

Russia's Defence Ministry says three people have been injured in an explosion inside an elite military academy in Russia's second-largest city.

Three people have been injured in an explosion in an elite military academy in Russia, the Defence Ministry said.

Officials said an unidentified "object" went off inside the prestigious Mozhaisky Academy in St Petersburg, which trains officers for the army's missile defence unit.

Three people suffered non-life-threatening injuries.

Live footage from outside the academy showed dozens of cadets being led out of the gated compound.