The teenagers, aged 14 and 16, opened fire with pneumatic guns at the nursery on Thursday morning, hitting a four year-old child. The child received slight injuries, and is now in a satisfactory condition.
The offenders have been detained and an investigation is to decide whether a criminal case should be launched.
Two attacks on children were reported earlier this year. In February 2007, a 50-year-old Belarusian with previous convictions fired shots at the window of a nursery. A week earlier, a man shot at children in a playground from his apartment window. No one was injured in these attacks, however.