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WASHINGTON, February 20 (RIA Novosti) New details about the death of a young Russian boy who died last month in Texas indicate the boy and his younger brother may have been playing alone outside their home before the older boy, 3-year-old Max Shatto, became unresponsive.

“We know the child was outside playing with the other child. They were both out there,” said Ector County, Texas Sheriff Mark Donaldson, according to the Odessa American newspaper.

“The mother went out there – she wasn’t out there – and when she came out there he was on the ground,” he added.

Donaldson’s office was notified at 4:49 p.m. CST (2249 GMT) on Jan. 21. By the time his deputies arrived, he said, the ambulance was transporting the boy to the Medical Center Hospital emergency room, where he was pronounced dead about an hour later.

Alan and Laura Shatto adopted Max and his brother from Russia in November.  The boy’s death has sparked outrage among many Russians.

Russia’s child rights ombudsman, Pavel Astakhov, tweeted on Monday that Max Shatto, also known by his Russian name Maxim Kuzmin, had “numerous injuries,” was given powerful “psychotropic substances,” and had been murdered by his adoptive mother.

Later Astakhov admitted the investigation into Shatto’s death has not been completed.

More than 60,000 Russian children have been adopted by Americans since the early 1990s, according to the US State Department. Russian officials say that, of these, 19 have died as a direct result of actions by their adoptive parents.

Russian lawmakers say they suspect many more adopted Russian children are abused after they arrive in the United States. Russia banned adoptions by Americans beginning on January 1.

“My interest here to start off with is a 3-year-old boy that’s dead,” Donaldson said. “And as far as I’m concerned, he’s a Texas boy because he’s living in the state of Texas and Ector County.”

An investigator with the Ector County Medical Examiner’s Office told RIA Novosti the boy had bruises on his body, but she didn’t know if they were the result of routine child’s play or evidence of deeper injuries.

Donaldson did not discuss any injuries the boy had or how he might have been injured.

The results of an autopsy are expected in about two weeks.