A police cordon is in place in Liskeard town centre, with officers guarding a scene along Dean Street.
Blue and white police tape has been erected around a garden area and a neighbouring shelter, stretching from the Early's letting agency towards the public toilet block.
The area remains closed to the public while police activity continues.
Items could be seen inside the shelter behind the cordon, including what appeared to be sleeping bags.
Forensic officers are also understood to be working in and around a property close to Baytree Hill.
The nature of the incident has not yet been confirmed by police.
Further details are expected as the investigation continues.
Liskeard Town Centre Incident Leads to Police Cordon