An outbuilding behind a Royal Mail sorting office has been broken into during a burglary in Radlett.
The incident took place in Watling Street at some time between 6pm on Thursday, March 9, and 5am on Friday, March 10.
According to Hertfordshire police, the outbuilding was broken into but nothing was taken.
PC Michael Morris said: "Thankfully, the offender(s) left empty-handed, and our enquiries are continuing at this time to trace them.
“I am appealing for anyone with information which may assist us to please come forward.
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"Did you witness any suspicious activity in the area?
"Have you captured something of note on a dash cam?
"Any information at all could prove key to progressing enquiries.”
PC Morris can be contacted via the following email: michael.morris@herts.police.uk
Information can be reported online at herts.police.uk/report or by calling the non-emergency number 101, quoting crime reference 41/19900/23.
Anonymous information can be given by contacting the Crimestoppers charity on 0800 555 111, or online at crimestoppers-uk.org.