Russian police say they have arrested a high school student who reportedly shot his way into a high school on the outskirts of Moscow, taking more than 20 students hostage.

A teacher and a police officer were killed in the incident, although the hostages were freed unharmed.

“The person who took 20 people and a teacher hostage is a student in the upper classes at the same school. He has been neutralised and all the students have been freed,” Interior Ministry spokesman Andrei Pilipchuk said on state TV. “One policeman was fatally wounded during the operation and died in hospital, and a teacher at School No. 263 was also killed.”

The gunman is said by police sources to have walked into the school with a rifle and kept his hostages in a biology classroom before being “neutralised” by armed officers.

Russian Interior Minister, Vladimir Kolokolstev is said to be on his way to the site.