At least seven children and a teacher have been killed in a shooting at a school in the Russian city of Kazan, officials say.
More than 20 others, mostly children, were reportedly wounded.
Footage shared on social media showed some children jumping from windows to escape as well as injured people being evacuated.
Russian TV reported that two of the children died after jumping from a second-floor window.
Rustam Minnikhanov, governor of the Tatarstan republic, of which Kazan is the capital, said that four male and three female students had died in Tuesday’s shooting.
According to the Interfax news agency, two gunmen opened fire in the school, while other reports said the attack was carried out by a lone shooter.
Social media footage showed a young man being pinned to the ground outside the school building by a police officer.
“The terrorist has been arrested, (he is) 19 years old. A firearm is registered in his name. Other accomplices haven’t been established, an investigation is under way,” Minnikhanov said after visiting the school on Tuesday.
It was not clear whether any other shooters remained at large.
Responding to the shooting, Russian President Vladimir Putin said he would review the country’s gun control laws.