Aleksandr Koptsev had been convicted of attempted murder and sentenced to 13 years in prison for stabbing nine worshippers with a hunting knife.
Koptsev's lawyers had appealed the sentence, arguing their client was mentally unstable.
Prosecutors also filed an appeal, asking for the inclusion of a charge -- dropped from the original trial -- of inciting interethnic hatred.
A spokesman for the Supreme Court said the reasoning for today's decision would be made public at a later time.
Russia has seen a wave of attacks in recent months targeting religious and ethnic minorities. Activists have accused authorities of failing to prosecute hate crimes.
(ITAR-TASS, Interfax, AP)
Yusuf Sultonov, whose 9-year-old daughter was beaten and stabbed to death in St. Petersburg on February 9, 2004 (TASS)
EXTREMISM ASCENDANT: More than half of Russians have xenophobic views, according to a report published in August 2005. In the report, rights groups say that -- despite progress in some areas -- racism, xenophobia, and anti-Semitism remain rife in Russia. But what worries watchdogs most are recent moves by nationalist-patriotic movements to form paramilitary groups....(more)
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