A number of caravans have pitched up at Ipswich's Portman Road Car Park.
The caravans were spotted in the car park, run by Ipswich Borough Council, on Sunday afternoon.
One nearby resident said they saw at least half a dozen spaced across the car park, opposite the football stadium.
Much of the car park is currently being used as a local coronavirus testing site, open from 8am to 8pm seven days a week.
A spokesman for Ipswich Borough Council said it is working with partners to resolve the issue.
The spokesman said: "We are aware of the situation and taking all the necessary and normal steps, along with our partners, to secure possession of the site."
A group of travellers were handed an eviction notice last summer after parking their caravans at the same car park, after Ipswich Borough Council applied for a notice from Suffolk Magistrates’ Court.
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