The head was from a 3 or 4-year-old girl whose body had been discovered in a nearby apartment in north-west Moscow after a fire was extinguished there. “Having waited for the parents to leave the flat with their older child, she killed the child for unknown reasons, started the flat on fire and fled,” the Russian investigators said in a statement. No explosives were found on her when she was in the street. The motive for the killing is unknown. The woman is undergoing psychiatric testing.The woman was later identified as 38-year-old Gyulchekhra Bobokulova, a native of ex-Soviet majority-Muslim Uzbekistan. Russia’s interior ministry declined to comment. An unnamed police source said the woman appeared to have been under the influence of psychotropic drugs.