"As of 10 a.m. Saturday [7:00GMT], 45 people have been receiving treatment, 25 of them are children," the Russian Health Ministry’s press office said in a statement.
Three people are in a critical condition, according to the press release. The condition of 10 others is assessed as serious.
READ MORE: Photos From Inside Kerch College After Deadly Blast Released
A fourth-year student exploded a bomb and opened fire on fellow students on Wednesday at Kerch Polytechnic, a vocational school for teenagers, killing 21 people and wounding over 50.
The attack, the first of its kind to hit Russia's Black Sea peninsula, was initially treated as an act of terrorism but was later reclassified as mass murder. The shooter killed himself in the college library.