Artur Sardaryan was killed on May 25, but his death was only announced today.
A spokeswoman for the Moscow region prosecutor's office says the group approached Sardaryan as he sat on a regional commuter train and stabbed him for no apparent reason.
A lawyer representing the family, Simon Tsaturyan, quotes eyewitnesses as saying the attackers shouted "Glory to Russia!"
Prosecutors have launched a hate-crime investigation.
The killing is the latest in a series of attacks on foreigners and immigrants from the Caucasus and Central Asia in Moscow and throughout Russia.
(compiled from agency reports)
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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