"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.
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.
"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."
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.
"Parents enter into it (foreign adoption) with positive motivations but, in a sense, they are a little bit blindsided by their desire to adopt," said LaBarbera, who specializes in the psychological evaluation of children and has worked with a number of children adopted from Russia and other foreign countries. "They're not prepared to appreciate, psychologically, the kinds of conditions these kids have been exposed to and the effect it has had on them."
Russian state television showed the child in a yellow jacket holding the hands of two chaperones as he left a police precinct and entered a van bound for a Moscow medical clinic.
The U.S. ambassador to Russia, John Beyrle, said he was "deeply shocked by the news" and "very angry that any family would act so callously toward a child that they had legally adopted."
Anna Orlova, a spokeswoman for Kremlin's Children Rights Commissioner, told The Associated Press that she visited the boy and he told her that his mother was "bad," "did not love him," and used to pull his hair.
Russian officials said he turned up at the door of the Russian Education and Science Ministry on Thursday afternoon accompanied by a Russian man who handed over the boy and his documents, then left, officials said. The child holds a Russian passport.
Rob Johnson, a spokesman for the Tennessee Department of Children's Services, said the agency is looking into Friday's allegations, although it does not handle international adoptions.
Bedford County Sheriff Randall Boyce also said Torry Hansen was under investigation and expected to interview her Friday afternoon.
Lavrov said his ministry would recommend that the U.S. and Russia hammer out an agreement before any new adoptions are allowed.
"We have taken the decision ... to suggest a freeze on any adoptions to American families until Russia and the U.S.A. sign an international agreement" on the conditions for adoptions, Lavrov said.
He said the U.S. had refused to negotiate such an accord in the past but "the recent event was the last straw."
Pavel Astakhov, the children rights commissioner, said in a televised interview that a treaty is vital to protect Russian citizens in other countries.
"How can we prosecute a person who abused the rights of a Russian child abroad? If there was an adoption treaty in place, we would have legal means to protect Russian children abroad," he said.
Julie Snyder, spokeswoman for World Association for Children and Parents in Renton, Washington, said the organization is limited to what it can say because of confidentiality restrictions. She said the group is working with authorities in the U.S. and Russia.
"It's as shocking to us as to anybody else to hear about it," she said.
Despite the uproar over adoptions, placing children inside Russia remains difficult. There are more than 740,000 children without parental custody in Russia, according to UNICEF, the United Nations Children's Fund.
United Airlines disavowed any responsibility and said it requires a parent or guardian dropping off a child for a flight to show an ID and to list who is picking the child up at the destination.
United spokeswoman Robin Urbanski said all unaccompanied minors on the flight that arrived Thursday in Moscow were picked up by the person listed on the form.
Previous adoption failures have increased Russian officials' wariness of adoptions to the U.S.
In 2006, Peggy Sue Hilt of Manassas, Virginia, was sentenced to 25 years in prison after being convicted of fatally beating a 2-year-old girl adopted from Siberia months earlier.
In 2008, Kimberly Emelyantsev of Tooele, Utah, was sentenced to 15 years after pleading guilty to killing a Russian infant in her care.
And in March of this year, prosecutors in Pennsylvania met with a Russian diplomats to discuss how to handle the case of a couple accused of killing their 7-year-old adopted Russian son at their home near the town of Dillsburg.
There is information and assistance available to people who want to become adoptive parents.
Texas Foster Care and Adoption