According to the committee investigating the incident, two of 24 wounded died from their injuries last night.
"17 people were killed, including 11 children and six adults," it said in a statement.
On Monday, a gunman opened fire in a school in the Udmurtia region, east of Moscow.
Twenty-four people, including 22 children and two teachers, were hospitalized, and they were in a serious or extremely serious condition, according to the committee.
The shooter was identified as Artyom Kazantsev, a graduate of the same school, and he was wearing a black t-shirt with Nazi symbols, the committee said.
Kazantsev used two traumatic guns reequipped for shooting with live ammunition.
He killed himself after committing the crime and his body was found at the school as well.
Some 982 children study and 80 teachers work in the school which is located near the city administration building in the center of Izhevsk.
