SAN CRISTOBAL (REUTERS) - Authorities are investigating claims that two men were murdered - mutilated by a confessed cannibal - then fed to fellow prisoners in a riot at a police detention center.

Families of the two victims, Anthony Correa and Juan Carlos Herrera, said they died earlier in October towards the end of a month-long siege at the overcrowded jail in the western city San Cristobal.

Correa's mother is now in hiding.

"My son was allegedly killed and tortured, and other detainees were forced to eat his flesh. How can you explain such cruelty, because while my son was there - he had a letter of good conduct," said mother of Correa, Luz Sepulveda.

Both families said a self-confessed serial killer Dorangel Vargas, known to Venezuelans as "People-Eater" had been used by a gang at the jail to dismember the bodies of their rivals.

The government has confirmed two deaths but not the circumstances.