Authorities have seized mobile phones and an internet dongle from the high-security Kot Bhalwal Central Jail on the outskirts of the city, officials said on Tuesday.
The seizures were made during a routine checking of the prison by the jail officials, they said.
Four mobiles and an internet dongle were hidden in a polythene bag near a washroom of a barrack, the officials said.
Authorities are investigating the matter and are checking the CCTV footage, they said.
The mobile phones have been handed over to the cyber crime department for further investigation, they said.