A 15-year-old boy who was a near straight-A student came to his school in northeast Moscow on Monday, February 3, took about 20 children hostage, fatally shot his geography teacher and a policeman with a rifle.

      The boy reportedly made his way into the school with a rifle by threatening a guard who immediately called the police. Investigators said the weapon belonged to the boy’s father.

      The teen barged into a classroom where his geography teacher was giving a lesson and fatally wounded him, then held about 20 his classmates hostage, authorities said. The gunman also shot a police officer who arrived on the scene and wounded another, police said.

      Investigative Committee spokesman Vladimir Markin said the boy fired at least 11 shots from one rifle. A police report said the boy had two rifles.

      The incident, which occurred at School 263 in the city’s Otradnoye district, came to an end when the boy’s father was brought to the scene and managed to convince his son to surrender. All hostages were released unharmed, police reported.

      The investigation currently can't find any reasons for the boy's violent behaviour. He is reported to be one of the best students in the class, who was never involved in any conflicts at school, including with the murdered teacher. One of the possible reasons at the moment is a nervous breakdown.

      However, the Kommersant newspaper have found anonymous sources who say the boy was angry at the teacher for preventing him from being awarded a gold medal for academic performance.

      Investigators have opened three criminal cases: for hostage-taking, murder and assault on a police officer. School shootings are one of the rarest crimes in Russia.