Memorial trees planted in memory of two women appear to have been deliberately snapped in half.
Two rowan trees close to the Barker Street entrance on to Marriott's Way in the city were vandalised last week.
The trees were funded by the county council and planted by Friends of Train Wood after they had been sourced by Matthew Davies of the Norwich Fringe Project.
They had been planted last September in memory of Margherita Colombo and Janice Middleton, two long-term Friends of Train Wood members, who both died in 2020.
The former had been a regular fixture on litter picks along Marriott's Way while the latter was the membership secretary for the Friends.
Maddy Goodall, chairwoman of the Friends of Train Wood and Marriott's Way, said: "To see the two rowans brutally snapped in half like this was heart-breaking.
"Sadly, they had already suffered as a result of the theft of their wooden trees guards soon after they were planted - which were later seen floating in the river.
"Although we'd tried to shore them up, the trees certainly couldn't withstand this, and it's deeply upsetting to think of someone putting such deliberate effort into destroying them."
Miss Goodall added: "This is an awful example of anti-social behaviour. It is not just an attack on nature but also the memory of these two people."
It is not known who is responsible and the damage is not believed to have been reported to police.
Miss Goodall and Mr Davies visited the damaged trees on Tuesday to move them and to set plans in place to source and plant two replacements.
This is expected to be completed either later this year or early in 2023.
The Friends of Train Wood group is considering replanting the trees next to the oak tree in memory of Adrian Holmes, former treasurer and founding member of the Friends.
This is located next to the old train shed where the plaques of Margherita and Janice are also located.
Chrissie Rumsby, Labour county councillor for the Mile Cross ward, said: "It is a great shame that this has happened and I will be contacting the highways tree officer to see if we can help get them replaced."
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