In August 1996, 74-year-old Tamara Vasilyevna Prosvirina, a pensioner residing in the village of Kaolinovyi near Kyshtym in Chelyabinsk Oblast in the Russian Urals, reported to local police that she had found and taken in a tiny humanoid creature — no more than 25 centimetres long — which she named Aleshenka ('little Alyosha') and which survived in her care for approximately three weeks before Prosvirina was committed to a psychiatric hospital for her apparent eccentricity and the creature was left to die. The remains — a skeleton with a prominent wedge-shaped skull, enormous eye sockets, delicate limbs, and anatomical features inconsistent with any known primate or human infant — were retained by local farm labourer Vladimir Nurtdinov and entered formal forensic analysis in 1997.
The Aleshenka remains were examined by Professor Stanislav Samoshkin, head of forensic medicine in Chelyabinsk; by Nikolai Novokonov, paramedic of the Kaolinov sanatorium; and by specialists at the Russian Center for UFO Research in Moscow. Analysis produced the consistent finding that the remains were not those of any known primate fetus or infant, did not match a stillborn human, did not match a deformed human, and showed bone density and cranial architecture inconsistent with any known earth species. A preliminary DNA analysis conducted in 1999 by researchers at Russia's Institute of Cytology and Genetics produced results that were reported as 'partial match to human with significant divergent sequences' — findings that subsequent Russian authorities attributed to sample contamination.
The Aleshenka remains disappeared in 2000 after they were taken from Nurtdinov's custody by investigators who did not return them. Prosvirina, whose testimony remains the only direct witness account, died in 1999 from injuries sustained when she was struck by a car. The case is widely regarded within Russian UFO and cryptid research as one of the most evidentially significant entity-specimen events of the twentieth century, and as one of the most suspicious evidence-disappearance incidents. It is routinely cited by Russian researchers including Vadim Chernobrov of Kosmopoisk as foundational to Russian anomalistic biology.