A cat detained at Sri Lanka’s main prison while allegedly trying to smuggle drugs and mobile phone SIM cards to inmates has escaped.

The feline was detected by jail intelligence officials on Saturday at the high-security Welikada Prison, a police official said.

He said nearly two grams of heroin, two SIM cards and a memory chip were found in a small plastic bag tied around the cat’s neck.

But it escaped on Sunday from a prison room where it was kept, Aruna newspaper said.

A Sri Lankan prison police officer in Colombo inspects a cat with a small plastic bag tied around its neck. Photo: EPA

There was no immediate comment from prison authorities.

The prison had reported an increase in incidents of people throwing small packets of drugs, mobile phones and phone chargers over the walls in recent weeks.

Sri Lanka is battling a major drug problem with some anti-narcotics detectives also implicated in selling confiscated drugs.

Police last week seized an eagle allegedly used by drug traffickers to distribute narcotics in a suburb of Colombo.