Max Shatto, a 3-year-old Russian adoptee who died last month in Texas, is now the center of an investigation over his American adoptive parents' role in his death.
Shatto, whose Russian name is Maxim Kuzmin, is believed to have suffered "inhuman abuse" at the hands of his parents, according to BBC News.
The investigation comes as Russia institutes a ban on US families adopting Russian children due to past abuses.
"Three-year-old Maxim was beaten (according to the investigators) by his adoptive mother, who fed him psychoactive drugs over a long period of time," ombudsman Pavel Astakhov tweeted, adding that he was dismayed the US State Department kept the case quiet, Agence France-Presse reported.
"He died before the arrival of the ambulance called by his adoptive mother. According to the autopsy report, the boy had many injuries," he said.
The US Embassy in Moscow responded to the allegations Tuesday, also via Twitter, where "US Kills Children" was the top trending hashtag in Russia, according to the Washington Post.
"State Department and local authorities have been working closely with the Russian Consulate in Houston for weeks," the tweet said.
“We deeply regret death of a child in Texas. A child’s loss of life is always a tragedy," said another. "It is important to wait for results of law enforcement investigation before drawing conclusions."
The boy was from the same orphanage as Chase Harrison, a Russian adoptee to North Virginian parents who died in July 2008 after his father left him in a hot car, the Post reported.
There have not yet been arrests in connection to Shatto's death, and officials were awaiting autopsy results, Sky News reported.
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