Michael and Nanette Craver of York County in Pennsylvania were sentenced Friday to the 19 months they have already spent in prison for the 2009 head-injury death of their adopted son Nathaniel, formerly Ivan Skorobogatov.
Russia's federal Investigative Committee said Saturday it will seek an international arrest warrant for the Cravers and will speed up an investigation to prove the boy was "brutally murdered."
The Cravers insist the boy suffered from fetal alcohol syndrome and attachment disorders. They claimed he ran headlong into a stove the night before they found him unconscious.
Defense lawyers said the couple had taken Nathaniel to numerous doctors and therapists because of the bizarre, self-abuse that left him badly bruised. Prosecutors, though, said they often failed to follow through on the treatment and therapy.
Prosecutors argued that the boy died from repeated blows to the head, but offered no theory at trial about which parent delivered them.