MOSCOW — Russian officials on Tuesday accused a Texas woman of fatally beating a 3-year-old boy she had adopted from Russia, setting off a new wave of outrage in a country already focused on American adoptions that have culminated in neglect or abuse.

Max Shatto and his younger brother left a Russian orphanage late last year with their adoptive parents, Laura and Alan Shatto, who live in the West Texas community of Gardendale.

On Jan. 21, the day Max died, Texas child welfare authorities received a report of his death, as well as accusations of physical abuse and neglect. A spokesman for the Texas Department of Family and Protective Services said on Tuesday that the death was being investigated. Senator Mary L. Landrieu, Democrat of Louisiana, said that the investigation would be completed in about two weeks and that appropriate actions would be taken.

The boy’s death shot to the top of the national news here on Tuesday, when Russia’s prosecutorial investigative committee opened a criminal inquiry into what it called “the murder of a 3-year-old Russian boy, Maksim Kuzmin, by his adoptive mother in the U.S.” Last year, President Vladimir V. Putin signed into law a ban on all adoptions by Americans, and scores of families are still hoping to complete adoptions that were in their final stages.

The United States Embassy in Moscow released a statement warning that “it would be irresponsible to draw conclusions about the death or assign guilt before autopsy results are analyzed and an investigation is carried out.”

But few seemed inclined to wait in Russia, where a prime-time news anchor called the boy “the 20th Russian child killed in the U.S.A. by his adoptive parents.” Politicians described the reaction of American officials as callous.

“Unfortunately, the death of a Russian child was not a tragedy for American congressmen, American senators, and in general it was not a tragedy for anyone in the States,” Olga Batalina, a lawmaker with the ruling party, United Russia, said in remarks to Parliament. “I propose that we pay tribute to a small Russian boy with a moment of silence.”

The boy’s death was reported in painful detail on Russian television throughout the day. One news broadcast illustrated its account with unrelated video clips showing adults hurting children — including one that circulated widely in 2011 of a woman in Alaska who punished her 7-year-old by forcing him to drink hot sauce.

“The information we received — I would stress once again, from the American authorities — is shocking,” Konstantin Dolgov, the Russian Foreign Ministry’s human rights commissioner, told the Voice of Russia radio station. “The 3-year-old boy has been repeatedly beaten by his American mother, and when the autopsy was performed, they found that his entire body was covered in bruises.”

He went on to say that Max had been given an antipsychotic medication that is prescribed for “very advanced forms of schizophrenia in adults.”

“We hope that if the investigation finds that his American parents are guilty of his killing — his assassination — we hope that, of course, they will be brought to justice,” he said.

The authorities in Texas were more cautious in their remarks, saying they were awaiting the results of an investigation. Patrick Crimmins of the Texas Department of Family and Protective Services said his agency had not received any previous accusations of abuse against the Shatto family, and declined to offer any details about signs of physical neglect or abuse.

“We may want to wait for a medical examiner’s report and/or toxicology results,” he said in a statement. In the meantime, he said, Max’s younger brother remains in the Shatto home. “We are monitoring the household to ensure his safety,” he said.

Whatever led to the boy’s death, it was an appalling end to an adoption. A triumphant note on Laura Shatto’s Facebook page last November celebrated her return to Texas with Max and his younger brother, Kirill, 2, whom the Shattos call Kristopher. Natalia Vishnevskaya, the head doctor at the orphanage in Pskov where they were adopted, told Russia’s Channel One that the boys’ biological mother took no interest in the boys’ lives and that her parental rights had been stripped when her sons were 1 and 2 years old.

She said the Shattos had visited the brothers repeatedly at the facility and never aroused any suspicions among the staff.

The Shattos have not given a public account of the boy’s death. A funeral home notice said he “passed into God’s arms on Monday afternoon, Jan. 21.” The obituary read, in part, “Max, you were not with us long enough to leave fingerprints on the walls, but you left fingerprints on our hearts.”

On Tuesday, no one responded to phone messages or answered a knock at the door of the family’s house in Gardendale, a rural unincorporated community with a population of 1,600. Two Russian television crews were among the journalists who had parked at an intersection near the house, which sits at the end of a gravel road.

Russia counts 19 children who have died because of abuse or neglect at the hands of American adoptive families. United States officials have made the case that these outcomes are exceedingly rare, saying that more than 60,000 Russian children have been adopted by American families over the last 20 years.

The idea of banning adoption of Russian children by Americans was not fully embraced by Russian leaders until late last year, when they were searching for a tough response to the Magnitsky Act, a United States measure targeting Russian officials accused of corruption and rights abuses.

The adoption ban was named after a 21-month-old, Dima Yakovlev, who died of heatstroke in Virginia in 2008 when his adoptive father left him in a parked vehicle for nine hours. Anger over adoption was revived in 2010 when a 7-year-old boy, born Artyom Solovyev, was sent alone on a flight back to Russia by his adoptive mother from Tennessee, along with a note saying the boy was “violent and has severe psychopathic issues.”

Reports of Max’s death on Tuesday prompted a number of new measures — most notably a temporary halt to all adoptions in the Pskov region, from which both Max and Dima Yakovlev had been adopted.

“A savage crime has been committed in America once again,” said the region’s governor, Andrei Turchak, according to the Interfax news service. He went on to say that his office would take immediate steps to return Max’s brother, Kirill, to Russia.

“Kirill cannot stay in the U.S. any longer,” Mr. Turchak said. “The child will simply change hands. American laws do not prohibit that. It will traumatize the child even more. He is not a dog or a car. Kirill must return to the Pskov region.”