A charity shop and businesses have been left hundreds of pounds out of pocket after locks have been filled with superglue around north Watford.
Police are investigating a string of incidents along St Albans Road between July 15 and Monday.
Among premise affected were along Car motorists supercentre between July 20 and 21, Age UK, between July 20 and 21 and Fresh Cut, between July 20 and 23.
The main locks or padlocks on the properties have been filled with superglue, causing the damage.
Deirdre Dent, neighbourhood inspector for Watford, said: "This is causing hundreds of pounds to the victims to repair, not to mention the inconvenience of having to install new locks.
"I would like to speak to anyone who has witnessed suspicious activity around these premises, or others in the area. Are you a local shop keeper and have been selling a large amount of glue to someone?
"This cannot continue, so I’d ask for the public’s support in being vigilant and contacting us with any information which could help us find who is responsible for these mindless acts of damage."
Anyone with information can contact the police via the non-emergency telephone number 101.
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