Police looking into what they describe as an alleged serious assault at a campground in Balclutha have completed their examination of the scene and are asking anyone with CCTV or dashcam footage from the surrounding streets to come forward.

Officers were called to the Balclutha Motor Camp, off Charlotte Street, at about 2.25pm on Sunday 1 November. Senior Sergeant Robin Hutton, who heads the police response team for the Balclutha area, said the victim was not physically hurt but was "incredibly shaken", and that police were providing support.

A scene guard stayed at the camp through Sunday night and specialist staff worked at the site on Monday. The Otago Daily Times reported police tape around part of the camp, a forensic tent set up beside a caravan and staff in protective suits.

On Tuesday afternoon police said the scene examination was complete and inquiries were continuing. They want to hear from anyone who was around Charlotte Street at any time on Saturday 31 October or Sunday 1 November and saw anything out of the ordinary, or who has security camera or dashcam footage covering that period.

Police have not said what the alleged assault involved, whether anyone has been identified or arrested, or given any description of a person they are looking for. The camp's manager told the ODT he had been asked by police not to comment while the investigation was under way.

Senior Sergeant Hutton said residents of the town should expect to see more police around in the coming days as the inquiry continues.

The motor camp is a regular stop for travellers on State Highway 1 between Dunedin and Invercargill and for people heading into the Catlins, and early November normally marks the start of the summer run of campervans through the town.

The case comes a fortnight after police in the same district appealed for help over an attack on three people in Sunderland Street, Clyde, which led to three arrests in Gore last week.

Anyone with information about the Balclutha incident can call police on 105 or report online at 105.police.govt.nz, and quote the file number 261101/7845. Crime Stoppers takes anonymous information on 0800 555 111.