Motorists using a busy Leyland car park got a nasty shock when five cars were clamped in just 15 minutes.
Clampers targeted vehicles parked on the Balfour Court car park next to Barclays Bank.
Michelle Gibson, 41, from Clayton-le-Woods, went into the bank for two minutes to return to find her car clamped.
She had to pay £80 to have the clamp released.
She admits she shouldn't have parked there, but said signs warning motorists it was for private use only were too high.
She said: "As soon as I turned my back, the clamp was on. I'm absolutely furious.
"There are some signs there but, like me, no one is aware of them.
"I saw five cars clamped in 15 minutes because we all missed it. People just don't realise."
Michelle claims the parking officer, from Preston-based National Clamps, was watching the drama unfold from his nearby van.
She said: "One lady could hear the chains from the clamp jangling before she even stepped into the bank.
"It was not until she came out that she realised what had happened. We were absolutely beside ourselves."
Michelle is warning others to be on their guard.
She said: "It's very rare I go into Leyland and it certainly won't encourage me to go again.
"I just want to make everyone aware of what they were doing.
"Not once did the man tell us we couldn't park there or warn us to move."
National Clamps declined to comment.
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