Seven schoolchildren have been killed and many more wounded after a lone teenage gunman opened fire in a school in the southwestern Russian city of Kazan, the head of the region says.
Two children could be seen leaping from the third floor of the four-storey School Number 175 to escape as gunshots rang out, in a video filmed by an onlooker and circulated by Russia's RIA news agency.
Calling the attack a big tragedy for the whole country, Rustam Minnikhanov, the head of the wider Tatarstan region, said there was no evidence that anyone else had been involved.
"We have lost seven children ... four boys and three girls," Minnikhanov told state TV.
"And 16 people, 12 children and four adults, are in hospital.
"The terrorist has been arrested. He's a 19-year-old who was officially registered as a gun owner."
It remains possible the death toll will rise, with Russian news agencies earlier citing a health ministry source saying at least 11 people had died.
Footage posted on social media showed a young man being pinned to the ground outside the school building by a police officer.
Video retweeted by BBC Russian correspondent Sarah Rainsford showed debris strewn through the school's corridors, as well as broken doors and walls.
Other video footage shared on social media showed emergency service vehicles parked outside the school, with people running towards the building.
Broken windows and debris outside also featured in footage shared online.
Kazan is the capital of the Muslim-majority region of Tatarstan and located around 800km east of Russia's capital, Moscow.
School shootings are rare in Russia. One of the last major incidents took place in Russian-annexed Crimea in 2018 when a student at a college killed 19 before turning his gun on himself.
Additional security measures had been enacted at other schools in Kazan, authorities said.
Kazan is 820km to the east of Russia's capital, Moscow.
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