Southern District Criminal Investigations Manager Detective Inspector Shona Low says a 25-year-old man has been remanded in custody and is due to reappear in Dunedin District Court on 21 October.

"During this time of day Great King Street, known to many as 'the one way north', is busy with cars and pedestrians, and we believe there is critical information that was recorded on dashcams, CCTV, or general photos and videos," she said.

"We are appealing to anyone who was on Great King Street, between Union Street West and St.David Street between 5am and 2.30pm on Friday, with a specific focus around 11am.

"We believe there is crucial information on any dascham, CCTV, or general photos and videos that were taken in this area, and we would like to hear from the public as soon as possible."

Police have created a dedicated web portal where people can upload photos or footage that was taken between 5am and 2.30pm on Friday 3 October in the Great King Street area.

Footage can be uploaded here: https://tex.nc3.govt.nz/.

Information can also be provided online through 105 online or via phone, or anonymously through Crime Stoppers on 0800 555 111.

Please use the reference number 251003/5165.

On Mondya, Judge Hermann Retzlaff directed that a report be prepared to explore the accused man's fitness and insanity under request from Counsel Anne Stevens KC, who also sought name suppression.

A mental health report will also be prepared.

The man was remanded in custody without plea until his next appearance in the Dunedin High Court on October 21.

The offence carries a maximum penalty of life imprisonment.

A neighbour told the Herald they were at home on Friday afternoon when they heard what they believed was a man's scream.

A scene guard was in place over the weekend as a forensic examination was carried out.