Police cordoned off a pathway in Tain yesterday as a forensic team carried out a search of the area.
Police closed off the narrow, well used walkway beside the Royal Academy buildings that links Hartfield Road and Scotsburn Road on the west side of town.
Last night, the force refused to comment on the nature of their investigations.
Local councillor and deputy leader of Highland Council Alasdair Rhind said: “There’s something going on, but we’ve had no word what it is. We’ve had no word from the police of the nature of the incident.
“I noticed this morning when I went down at 8am that the path had a police car at each end.
“When I went back down at 10.30am there was more police activity, I presume with CID, and there were reports of people going about in white boiler suits and police cars going about the area and officers speaking to people.”