Council bosses are taking legal action to remove a group of travellers from land on Moreton Hall, in Bury St Edmunds.
Ten caravans pitched up on Layhill Covert, off Symonds Road, on Friday afternoon - land which is the subject of a High Court injunction preventing unauthorised encampments.
St Edmundsbury Borough Council served the travellers with a letter at 6pm on Friday warning that they were in breach of the injunction and had 24 hours to vacate the site.
However, the travellers remain on the land and the council is continuing with legal proceedings to move them on.
A council spokeswoman said: “We want to reassure residents that everything possible is being done and if they want to report any security concerns call police on 101.”
The High Court injunction preventing unauthorised encampents covers Moreton Hall and town centre car parks.