The boy, Artyom Savelyev, was put on a plane by his adopted grandmother, Nancy Hansen of Shelbyville.
"He drew a picture of our house burning down and he'll tell anybody that he's going to burn our house down with us in it," she told The Associated Press in a telephone interview. "It got to be where you feared for your safety. It was terrible."
Russian Foreign Minister Sergey Lavrov called the actions by the grandmother "the last straw" in a string of U.S. adoptions gone wrong, including three in which Russian children had died in the U.S.
In an exclusive interview with ABC News' George Stephanopoulos, Dmitry Medvedev said the boy "fell into a very bad family."
"It is a monstrous deed on the part of his adoptive parents, to take the kid and virtually throw him out with the airplane in the opposite direction and to say,
'I'm sorry I could not cope with it, take everything back' is not only immoral but also against the law," Medvedev said.
The cases have prompted outrage in Russia, where foreign adoption failures are reported prominently. Russian main TV networks ran extensive reports on the latest incident in their main evening news shows.
The Russian education ministry immediately suspended the license of the group involved in the adoption
- the World Association for Children and Parents, a Renton, Washington-based agency
- for the duration of an investigation. In Tennessee, authorities were investigating the adoptive mother, Torry Hansen, 33.
Any possible freeze could affect hundreds of American families. Last year, nearly 1,600 Russian children were adopted in the United States, and more than 60,000 Russian orphans have been successfully adopted there, according to the National Council For Adoption, a U.S. adoption advocacy nonprofit group.
"We're obviously very troubled by it," U.S. State Department spokesman P.J. Crowley said in Washington when asked about the boy's case. He told reporters the U.S. and Russia share a responsibility for the child's safety and Washington will work closely with Moscow to make sure adoptions are legal and appropriately monitored.
Asked if he thought a suspension by Russia was warranted, Crowley said, "If Russia does suspend cooperation on the adoption, that is its right. These are Russian citizens."
"Child abandonment of any kind is reprehensible," said Chuck Johnson, acting CEO of the National Council For Adoption. "The actions of this mother are especially troubling because an already vulnerable, innocent child has been further victimized."
The boy arrived unaccompanied in Moscow on a United Airlines flight on Thursday from Washington. Social workers sent him to a Moscow hospital for a health checkup and criticized his adoptive mother for abandoning him.
The Kremlin children's rights office said the boy was carrying a letter from his adoptive mother saying she was returning him due to severe psychological problems.
"This child is mentally unstable. He is violent and has severe psychopathic issues," the letter said. "I was lied to and misled by the Russian Orphanage workers and director regarding his mental stability and other issues. ...
"After giving my best to this child, I am sorry to say that for the safety of my family, friends, and myself, I no longer wish to parent this child."
The boy was adopted in September from the town of Partizansk in Russia's Far East.
Nancy Hansen, the grandmother, told The Associated Press that she and the boy flew to Washington and she put the child on the plane with the note from her daughter. She vehemently rejected assertions of child abandonment by Russian authorities, saying he was watched over by a United Airlines stewardess and the family paid a man $200 to pick the boy up at the Moscow airport and take him to the Russian Education and Science Ministry.
Nancy Hansen said a social worker checked on the boy in January and reported to Russian authorities that there were no problems. But after that, the grandmother said incidents of hitting, kicking, spitting began to escalate, along with threats.
She said she and her daughter went to Russia together to adopt the boy, and she believes information about his behavioral problems was withheld from her daughter.
"The Russian orphanage officials completely lied to her because they wanted to get rid of him," Nancy Hansen said.
She said the boy was very skinny when they picked him up, and he told them he had been beaten with a broom handle at the orphanage.
Joseph LaBarbera, a clinical psychologist at Vanderbilt University Medical Center in Nashville, said adoptive parents are many times not aware of the psychological state of children put up for adoption.