Moscow - At least four prisoners were killed and eight others injured in a fire at a Russian prison, a prison spokesperson told Interfax news agency on Saturday.
Two of the injured were in critical condition following the incident in the city of Ulyanovsk some 700km east of Moscow.
Local media reported the fire may have broken out during a prison riot and that several prisoners reportedly fled during the fire.
Officials denied any prisoners had escaped and said the incident was under investigation.