Moscow has opened a criminal inquiry into the murder of a Russian boy adopted in the United States, Investigative Committee (IC) said Tuesday.
"The criminal case was opened under Article 105, murder charges of the Russian Penal Code," the official IC website said.
Investigators are going to ask the U.S. authorities to arrest the adoptive mother, Maxim Kuzmin, who lived in Ector County, Texas.
The mother, in absentia, was called by the Russians as L. Shatto.
"Investigative Committee will issue international search warrant for the boy's adoptive mother and demand Russian investigators take part in the criminal investigation on the U.S. territory," the IC said.
It added that Moscow would undertake all necessary measures to punish "severely" those responsible for the child's death.
Pavel Astakhov, the Russian presidential envoy for children's rights, said Monday that the boy died on Jan. 21 after being allegedly abused and fed with psychoactive drugs by L. Shatto.
This is the 20th death of Russian children in U.S. foster families since 1996.
Washington agreed to cooperate with Moscow earlier this month in investigating abuse of adopted Russian children in the United States.
President Vladimir Putin said on Feb. 9 that Russian orphans should be adopted in their homeland.
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