A crackdown on drugs being smuggled into Perth Prison was launched by police.
Police Scotland, in partnership with the Scottish Prison Service (SPS), has been working at HMP Perth to tackle illegal substances entering the prison.
Officers carried out patrols around the perimeter of the jail and the surrounding areas.
Specialist resources, including dog units, were deployed throughout the operation to deter any offending.
Police said that as a result of the activity - which took place on Wednesday, January 25 and Thursday, January 26 - there were no crimes detected.
They said that officers spoke to local people to advise that further operations will be carried out in the future without warning.
Police constable Scott Birrell, prison liaison officer, said: “Tackling drug misuse within prisons is a priority for Police Scotland and this operation reinforces our determination to target criminals.
“Drug misuse brings nothing but misery and people’s lives can be ruined.
“We will continue to use every tool and tactic at our disposal to remove these illegal substances from our prisons.
“We depend on the continued support from our partners and our local communities and I would urge anyone who has any information, or concerns surrounding drugs, to contact police.
“Anyone with concerns can call officers on 101 or alternatively, call Crimestoppers anonymously on 0800 555 111.”
An SPS spokesperson said: “The SPS is committed to tackling the harms caused by misuse of contraband substances in our prisons.
“We have invested in technology to better detect suspicious substances, working closely with partner agencies to gather relevant intelligence.
“Rapiscan machines which specifically detect substances that may be concealed in items of mail and personal property, are now in use in all of Scotland’s prison.
“Individuals will use various methods, including drones, in an attempt to introduce contraband to our prisons.”
The spokesperson added: “We deploy a range of robust security measures to prevent this and work closely with Police Scotland to investigate and identify any perpetrators.”
