A gunman with a swastika on his teeshirt killed 13 people, including seven children, and wounded more than 20 at a school in Russia on Monday before committing suicide, investigators said.

The identity of the attacker and the motive for the shooting in Izhevsk, about 970 km (600 miles) east of Moscow, were not clear.

Russia's Investigative Committee, which handles major crimes, said the gunman was wearing a balaclava. It released a short video showing his body lying on the floor of a classroom with overturned furniture and papers strewn on the floor. He was dressed all in black, with a red swastika in a circle drawn on his teeshirt.

The committee said the six adult victims included teachers and security guards. It said 21 people, including 14 children, were wounded.

Tass news agency quoted investigators as saying the attacker was armed with two pistols and a large supply of ammunition.

Russia has seen several school shootings in recent years.

In May 2021, a teenage gunman killed seven children and two adults in the city of Kazan. In April 2022, an armed man killed two children and a teacher at a kindergarten in the central Ulyanovsk region before committing suicide.