Officials in West Texas said Monday they are investigating the "suspicious" death of a 3-year-old boy, adopted from Russia, the same day a Russian official blamed the death on "inhuman abuse."
The boy was born on January 9, 2010, and died on January 21, 2013, according to Konstantin Dolgov, the Russian Foreign Ministry's special representative for human rights.
"I would like to draw your attention to another case of inhuman abuse of a Russian child by U.S. adoptive parents," he said in a statement.
Dolgov claimed the child suffered injuries to his head and legs, as well as to his abdomen and internal organs. The wounds, he said, "could only be caused by strong blows."
Kim Herrington, an investigator with the Ector County Medical Examiner's Office, said the case was referred to his office because of the "suspicious" nature of the child's death.
Patrick Crimmins, of Texas Child Protective Services, said his office is investigating. The allegations include physical abuse and neglectful supervision, or neglect, he said.
Sgt. Gary Duesler, spokesman for the Ector County Sheriff's Office, said his office is also investigating. No arrests have been made, and officials are waiting for autopsy results, he said.
A call seeking comment to a number listed for the boy's adoptive parents was not immediately returned. A voice message told reporters they would have no comment.
The child's death comes amid tension between the United States and Russia over adoptions.
U.S. State Department spokeswoman Victoria Nuland said Monday that officials are aware of the case.
"The Department of State takes very seriously the welfare of children, particularly children who have been adopted from other countries," she said. "We will continue to assist the Russian Embassy and consulate officials in making contact with the appropriate authorities in Texas."
In December, Russian President Vladimir Putin signed into law a measure that would ban the adoption of Russian children by U.S. families. It is scheduled to take effect in January.
The action could affect hundreds of U.S. families seeking to adopt. Americans adopted close to 1,000 Russian children last year, according to U.S. State Department figures.
Though the number has been dropping in recent years, Russia remains the third most-popular foreign country - after China and Ethiopia - for U.S. foreign adoptions.
The Russian measure also bars any political activities by nongovernmental organizations receiving funding from the United States, if such activities could affect Russian interests, Russia's semiofficial RIA Novosti news agency said.
And it imposes sanctions against U.S. officials thought to have violated human rights.
The move is widely seen as retaliation for a bill that U.S. President Barack Obama signed into law on December 14. That law, called the Magnitsky Act, imposes U.S. travel and financial restrictions on human rights abusers in Russia.
The Magnitsky Act is named for Russian lawyer Sergei Magnitsky, who uncovered the largest tax fraud in the country's history in the form of rebates claimed by government officials who stole money from the state. Magnitsky was apparently beaten to death in 2009 after a year in a Moscow detention center.
Backers of the Russian bill said American adoptive parents have been abusive, citing what they say are 19 deaths of adopted Russian children since the 1990s.
The Russian public supported the bill, with 56% of respondents in a poll conducted by the Public Opinion Foundation (FOM) saying they backed the ban, RIA Novosti reported.
In 2010, an American woman sparked outrage after she sent her adopted son back to Russia alone on a one-way flight, saying the boy, then 7, had violent episodes that made her family fear for its safety.