Rabbi Yaskov is a Chabad emissary in Derbent in the Dagestan region in Russia.
According to some reports, he was shot by a group of men, while others attributed the shooting to a single man. The attacker or attackers fled the scene before police arrived.
Police believe the attack was motivated by anti-Semitism. Dagestan has suffered frequent terrorist violence in recent years, much of it due to the Islamist group Shariat Jamaat and to clashes between Sufi and Salafi Muslim groups.
Rabbi Yaskov was taken to a local hospital in serious condition, and remains in intensive care.
Rabbi Yaskov is a former student at the Moscow Yeshiva and is close to Rabbi Berel Lazar, the Chief Rabbi of Russia. He has four children.
Last year a young Jewish man was murdered in Moscow when he attempted to prevent violence between two gangs.