Detectives in Bury St Edmunds are appealing for witnesses after two men reported being threatened by a man with a gun on the Mildenhall estate.
At just before 5pm yesterday, the two men ran into the post office, in Lake Avenue asking for help, claiming that a man had pointed a gun at them through a car window.
Police officers carried out a search of the area and recovered a firearm in the grounds of a hotel on Mildenhall Road.
They arrested three people nearby within the hour, all on suspicion of possessing a firearm with intent to cause fear or violence.
Two men aged in their 20s and a 16-year-old boy were taken to Bury St Edmunds Police Investigation Centre for questioning, where they have been bailed to return on Wednesday October 29 pending further enquiries.
Police are looking to speak with anyone who saw a blue sports car either around the Mildenhall estate or at the Tollgate crossroads, junction of Mildenhall Road and Thetford Road, between 4.30-5.30pm yesterday afternoon.
Calls should be made to Bury St Edmunds CID on 101 quoting reference BU/14/2670, or Crimestoppers anonymously on 0800 555 111.
Police are not linking this incident with the armed robbery at Hardwick Convenience Stores, in Home Farm Lane later the same night.