A group of travellers have settled on the Kingfisher Leisure Centre car park and the bus and lorry stop-over in Sudbury.
On Saturday afternoon the large group moved into the Babergh District Council owned car parks by Waitrose at the end of Great Eastern Road.
A spokesman for the group said they would be looking to move on from the site in the next few days.
He added: “We have been using the local pubs, the leisure centre and the shops.”
John Sayers, Suffolk county councillor for Sudbury told the Free Press he was concerned about the cost and amount of time that would be taken to move the families from the site.
“Maybe they are just going to be here for a few days and then be on their way,” he said.
“If longer the whole process of getting them out will be a long and costly process.
With such a large number of caravans being moved onto the site Mr Sayers described it as “more of an invasion”.
Mr Sayers highlighted to problem of lost parking for residents and visitors to the town and the loss of the stop-over area.
There have been warnings that this may delay some bus services.
A Babergh District Council spokesperson said: “We are aware of the unauthorised encampment in the car park near to the Kingfisher Leisure Centre and Waitrose.
“This is being dealt with in accordance to the Suffolk-wide protocols on unauthorised encampments and in partnership with ourselves, the Gypsy and Traveller Liaison Service and Suffolk Constabulary.”