Mobile sets were on Wednesday recovered from inmates of a special jail in Rourkela, police said.
Acting on a tip-off, Superintendent of police Ravi Kant raided different cells and seized mobile sets which were kept in secret places.
Stringent action would be taken against the jail staff and others involved in the incident after investigation, Kant told PTI.
In another incident, three youths were arrested for allegedly raping an unmarried girl here in Sundergarh district today.
The accused took advantage of her being alone in her uncle's residence and raped her.
The youths were identified as Bisra Oram, Sahadev Bhumij and Chaitu Oram, residents of the same village.