"12 children remain in the hospital of the DRKB, their condition is assessed as stable, without negative dynamics," the TASS press service quotes.
After the completion of the treatment, a girl born in 2008 was discharged in satisfactory condition.
Previously, two boys born in 2012 and 2013 were discharged.
The head of the Russian Ministry of Health, Mikhail Murashko, said that two children remain in serious condition.
On May 11, as a result of the shooting in the Kazan gymnasium No. 175, seven children and two teachers were killed, another 23 people were hospitalized.
Suspect Ilnaz Galyaviev, born in 2001, was detained and later arrested. He fully admitted guilt.