Police were called to the Ascot Oamaru Motel next to the Galleon Family Complex between Redcastle Rd and Fernbrook Rd, on State Highway 1, about 8.10pm.
It is alleged a man being sought by police, described as being a Polynesian of solid build wearing a black shirt, black puffer jacket and blue jeans, entered the motel's reception area before he threatened staff with a weapon and demanded they open the cash register.
The manager of the motel, who did not wish to be named, said he was ''still dealing with the situation'' and that the staff involved did as they were asked, which resulted in the man fleeing the scene with a ''minimal amount of cash''.
Senior Sergeant Jason McCoy, of Oamaru, said he was unable to confirm what kind of weapon was used.
It is believed the man might have had an accomplice who waited outside while the robbery was carried out.
Snr Sgt McCoy said a team from Dunedin travelled to Oamaru yesterday to conduct a scene examination.
Inquiries are continuing.
-Oamaru police (03) 433-1400, Crimestoppers 0800 555 111.
