Foreign Minister Sergei Lavrov has said that adoptions of Russian children by US parents may be halted after a seven-year-old boy was put on a plane back to Moscow alone when his adoptive mother said she "no longer wanted to parent him".
Artyom was taken on Thursday afternoon from Sheremetyevo Airport to the headquarters of the Child Protection Agency in Moscow, and left there with a note asking for his adoption to be revoked.
"This child is mentally unstable," the adoptive mother, 27-year-old Torry Hansen, of Shelbyville, Tennessee, wrote in a typed letter. "After giving my best to this child....I no longer wish to parent him."
Larisa Bondaryova, a representative of Russia's Child Protection Agency, said Artyom was "under the impression that he was coming for a visit, which he was happy about. He still hasn't grasped what all has happened to him."
On Friday evening, Artyom's adoptive grandmother, Nancy Hansen, told CNN television that she was the one who put him on the plane.
She says she did not abandon Artyom, who was called Justin by his adoptive family, but "followed instructions of a lawyer that she found online" and arranged for him to be looked after on the flight by airline staff and picked up at Sheremetyevo by a "reliable" driver.
Nancy Hansen said Artyom was angry with his adoptive mother, and it was the "violent tendencies" that made them decide to return him. "He had to be watched at all times," said Hansen, adding that the final straw had come on Monday when Artyom tried to set a fire in his room.
Tennessee newspaper The Shelbyville Times-Gazette reported that Artyom's adoptive mother, Torry Hansen, could not be reached on Friday.
Authorities may review the license of the Russian agency that facilitated the adoption, Russian media reported.
Foreign Minister Lavrov on Friday called for a new agreement with the United States detailing the responsibility of adoptive parents, and said adoption of Russian children by American parents should be put on hold until such an agreement was reached.
President Dmitry Medvedev reacted angrily to the case, calling the actions of the adoptive parents "immoral" and "monstrous ... to take the kid and virtually throw him out" in an interview with ABC News.
A US State Department spokesman said Washington was "very troubled" by the incident, CNN reported.
In Moscow, Artyom was reported to have spoken well of his adoptive grandparents, but when asked to talk about his mother, his eyes filled up with tears. Artyom also spoke well of his adoptive brother, 10-year-old Logan, Hansen's biological child. Both children were taught at home.
Artyom told Russian authorities that Torry Hansen did not beat him but often would pull his hair, RIA Novosti reported. Artyom was born in Lesozavodsk, in the Primorsk region of Far Eastern Russia. His biological mother gave him up for adoption two years ago and he was placed in a Russian orphanage.
Torry Hansen, who is believed to be single and working as a nurse, adopted Artyom six months ago and took him to the United States.
She had only spent four days getting to know Artyom prior to securing the adoption, according to several Russia media reports.
"We are at loss as to how this woman was allowed to adopt a child, because usually preference is given to families that have two parents," said Russia's ombudsman for children's rights, Pavel Astakhov.
he US ambassador to Russia, John Beyrle, was quoted by CNN as saying that Washington would investigate "the circumstances of the boy's return to see if any crimes were committed", and added that "we know he is being well cared for".
Russian authorities say they are keen to find a foster family to take in Artyom.
Failing that he could return to his original orphanage, or move to a new one overseen by the Foreign Ministry.
Currently, Artyom is in hospital undergoing checks.
"He appears to be in good condition, but he is quite down psychologically," said the head of the hospital, Anatoly Egorenkov.