Eleven people, including nine children, have been killed in a shooting at a school in the Russian city of Kazan, reports say.
Two gunmen reportedly opened fire inside the school, some 820km (510 miles) east of Moscow.
A teenager was detained, while reports said a second assailant was killed in the building.
Authorities said security had been restored at the school in Kazan, in the mainly Muslim republic of Tatarstan.
Police have opened an investigation. No motive has yet been established.
Heavily armed police and emergency vehicles responded to the shooting at School No. 175 on Tuesday.
Footage shared on social media showed some children jumping from windows to escape as well as injured people being evacuated.
atarstan President Rustam Minnikhanov described the shooting as a “disaster” and a “tragedy”.
He told reporters outside the school that 12 children and four adults were being treated in hospital.
“The terrorist has been arrested. He’s 19. He’s a registered firearm owner,” he said.