MOSCOW: Russia has voiced skepticism about the U.S. autopsy on a 3-year-old adopted Russian boy in Texas and demanded further investigation.

Max Shatto's death, ruled accidental, came a month after Moscow passed a ban on international adoptions in retaliation for a new U.S. law targeting alleged Russian human rights violators. Russian officials have pointed at Max's case to defend the ban, which has drawn public criticism.

Max, born Maxim Kuzmin, died Jan. 21 after his adopted mother told authorities she found him unresponsive outside their home where he had been playing with his younger brother.

Foreign Ministry rights envoy Konstantin Dolgov said Saturday that Moscow "proceeds from the understanding that these are the preliminary results of the investigation" and urged U.S. authorities to produce autopsy documents and the boy's Russian passport.