Discarded e-scooters are posing a danger to disabled people in Newcastle, a campaign group has said.
Newcastle City Council has been trialling the use of rentable scooters since February 2021.
Blindness campaigner Sarah Gayton said she was "shocked" to find "dumped" scooters "creating dangerous trip hazards" during a visit to the city.
The council and scooter firm Neuron said the scheme was a success and problems were being dealt with.
Ms Gayton, a street access campaigner for the National Federation of the Blind of the UK (NFBUK), said on a visit to Newcastle earlier this month she found scooters creating "obstructions for any blind, visually impaired, older and disabled people".
She said she also experienced people riding them on pavements past her which was "frightening".
Ms Gayton said: "The trial has been operating for a long time and it is clear it has failed to protect the safety and accessibility of disabled pedestrians and it needs to be closed down immediately."
She described the condition of some e-scooter helmets and tyres as "scandalous".
She claimed to have found tyres "with no tread" and helmets "smashed, broken and dented lying on the floor".
Neuron Mobility, the firm responsible for the scooters, said it worked with disability groups to "promote safer streets" and offered an "online riding school" for users.
A spokesman said riders were required to park at designated spots controlled by "geofencing" and scooters were fitted with "topple detection" to "alert our operations team if they have been left on their side".
He added that reports of bad parking were dealt with swiftly but it was impossible to "eliminate bad parking and riding entirely".
Neuron said its scooters were built to a "higher standard" than privately owned ones and were inspected every three days as a minimum, while riders were "incentivised" to wear helmets.
It also said vandalism was "rare" and damaged scooters were removed from the streets for repairs.
A Newcastle City Council spokeswoman said there had been some "concerns" about scooters not being used or parked in a "considerate manner" and changes had been made including the use of new technology to "better control where the e-scooters are ridden and parked".
She said it was one of a number of similar trials across the country on behalf of the government to "gather information and evidence to inform a national decision on whether e-scooters could become a legalised form of transport".
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