Police in Cardiff Bay have seized more than 40 illegal e-bikes and scooters in just one week.
Neighbourhood officers say the MPVs (mechanically propelled vehicles), which had been illegally adapted, will be sent for destruction.
In total, 31 e-bikes and 11 scooters were seized in the Butetown and Grangetown areas.
Sergeant Samantha Johnson from South Wales Police said: "We’re committed to keeping our streets safe. We will not tolerate illegal activity in our communities."
"Unlawful use of e-bikes and e-scooters is not only illegal but also puts pedestrians and road users at serious risk. We urge the public to understand the law and make safe, legal choices."

Last month, a series of joint operations involving South Wales Police, Cardiff Council and immigration officers led to over 135 MPVs being taken off the streets in the Canton and Cathays areas of the city.
On average, the confisfacted bikes were able to reach speeds of between 25 and 70mph - the legal limit is 15.5mph - with one MPV able to reach a top speed of 84mph.
Two men were also arrested for possessing Class A drugs and a pointed blade.
South Wales Police said they had noticed an improvement in compliance with the law for e-bike users, and a significant decrease in those using illegal and modified e-bikes in the area.

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