Two men were refused entry into a prison in Perth following detection by drugs dogs.
It comes after a joint operation was launched with specialist resources, Operational Support Unit and Roads Policing Unit and the local community policing team to tackle drugs entering the prison.
Inappropriate behaviour towards staff at HMP Perth was also the target of the operation.
Last week, two men aged 24 and 26 were separately refused entry into the prison after detection from SPS drug dogs.
Meanwhile a 30-year-old man was cautioned and charged in connection with threatening and abusive behaviour and a 40-year-old woman was issued a warning in connection with threatening and abusive behaviour.
Officers have been carrying out covert and high-visibility patrols at HMP Perth as part of continued work with the Scottish Prison Service (SPS) to deter and detect illegal activity.
Police constable Scott Birrell, Prison Liaison officer, said: “We have routine policing patrols and work in partnership with the Scottish Prison Service to deter criminal activity within prisons.
“High visibility and covert operations can be carried out without warning and we will continue to use all available tools and tactics to remove illegal substances from our prisons and address associated criminality.
“Information and support from our partners and the public is vital as we work to make our communities safer. I would urge anyone who has any information or concerns to contact police. Information can be passed to us via 101 or to Crimestoppers anonymously on 0800 555 111.”
A Scottish Prison Service spokesperson said: “Ensuring the safety and wellbeing of those who live and work in our prisons is one of our key priorities.
“We are committed to tackling the harms caused by the introduction of illicit substances, and the associated criminality which comes with them.
“We deploy a range of robust security measures to prevent this, and work closely with Police Scotland to investigate and identify any perpetrators.”
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