The zoo workers in Kaliningrad said the man told a ticket collector he had to get into the facility after closing time Wednesday because "he's expected" and forced his way onto the premises, RIA Novosti reported Thursday.
A zoo worker discovered the man naked by the tiger cage the following day, with his clothes inside the enclosure. The zoo called police and an ambulance, which took the man to a local hospital to be checked out.
The man was allowed to go home after he was found to be in sound mental health and not under the influence of alcohol or drugs.
No explanation was given for the man's behavior, but one of the doctors who treated him asked, "Who hasn't done stupid things in their youth?"