MOSCOW: Moscow should "temper emotions" over the death of a Russian boy adopted by an American family, President Vladimir Putin's spokesman said Friday after the U.S. ambassador urged Russian authorities and the media to stop their "sensational exploitations" of the case.

Spokesman Dmitry Peskov said the harsh statements by Russian officials and lawmakers were driven by the "zero tolerance" of Russians to the deaths of children adopted by Americans. Still, he acknowledged it's too early to know the cause of the Jan. 21 death of 3-year-old Max Shatto, born Maxim Kuzmin, in West Texas.

"I think it's necessary to temper emotions a bit," Peskov said on independent Rain TV. "One thing is obvious and undisputable: bruises were found on the child's body. We hope that forensic experts will determine their origin."

The medical examiner's office in West Texas has not officially pronounced the cause of death and presented only early results, but its report of bruises on Max's body - although their origin has not been established - has prompted some Russians to jump to conclusions.

Russian children's rights ombudsman Pavel Astakhov branded the death as a "killing" by his adoptive American mother, Laura Shatto. The State Duma's petition to the U.S. Congress on Friday said the death is "connected to the fact of violence" by the Shattos.

The Russian theory that the boy was killed has topped the news on state-controlled media, which have been using the case to justify Russia's Dec. 28 move to ban all adoptions by Americans. The ban sparked criticism abroad and a protest rally in Moscow.

U.S. Ambassador Michael McFaul said he was "troubled by how my people and my country are being portrayed by some in the Russian press."

"It is time for sensational exploitations of human tragedy to end and for professional work between our two countries to grow, on this issue and many others," he wrote in a blog post Friday.

Texas authorities said this week that Max's adoptive mother told them that Max and his half-brother were playing outside the family's home near Odessa, Texas. Shatto said she came out and found the boy unconscious on the ground.

Shirley Standefer, the chief investigator for the Ector County Medical Examiner's Office, said there were signs of bruising on Max's lower abdominal area, but added that a full autopsy would be needed to determine what kind of bruising that was. Authorities also have not received a toxicology report that would have details on whether Max was being given any medication.

The Texas Child Protective Services spokesman said that they had received allegations of physical abuse and neglect, but had not determined whether those allegations were true.

Russia's state-controlled Rossiya TV channel aired a live talk show Thursday featuring the biological mother of the boy, Yulia Kuzmina, who lost parental custody for Max and his half-brother Kirill Kuzmin over negligence and serious drinking problems.

In a tightly choreographed interview, Kuzmina insisted that Russian custody officials took advantage of her absence from her hometown to seize her children. The program's host Mikhail Zelenin introduced Kuzmina as "mourning for Maxim and hoping to get Kirill back." The experts commenting on the case were largely Kremlin loyalists, including author Maria Arbatova, who insisted that Kuzmina's children were "stolen" from their mother.

Kuzmina said she gave up drinking, had found a job and pledged to fight to get back Kirill.

Valentina Chernova from the children's welfare office said on the talk show that Kuzmina was stripped of custody for drinking bouts during her pregnancy and her negligence with her first-born.

The RIA Novosti and Interfax news agencies reported Friday that Kuzmina and her boyfriend, who were traveling Thursday night from Moscow to their home town, were taken off the train by police after a drunken brawl.

Peskov said a court will "take into account all the information about what kind of mother she is."