An Asda store in Wrexham has installed an £80,000 fleet of trolleys - complete with radar system to deter thieves.
Trolleys: The store has spent £80,000 on a new fleet
When trolleys cross a designated perimeter outside the store, a brake is triggered which brings it to a stop.
The system uses a series of radio waves to trigger the brake system which can only be unlocked by staff.
Staff at the store said up to 100 trolleys were going missing every week, costing them thousands of pounds and posing a hazard for the public.
An Asda spokeswoman said the system was operating successfully after being switched on this week.
She said: "Within five minutes of switching the system on, we had stopped our first trolley."
The spokeswoman added: "We were having to hire vans every fortnight to pick up the missing trolleys.
"We were collecting between 50 and 200 every time.
"People would push their shopping home, then dump trolleys in other people's gardens - which is awful for local residents and also very dangerous."