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 a Polynesian of solid build wearing a black shirt, black puffer jacket and blue jeans, threatened staff with a weapon and demanded they open the cash register.
A police spokeswoman said yesterday police were continuing to investigate the incident and no arrests had been made.
Speaking the day after the robbery, the motel manager, who did not wish to be named, said staff involved did as they were asked and the man fled 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 was believed the man might have had an accomplice who waited outside while the robbery was carried out.
A team from Dunedin conducted a scene examination this week.
• Oamaru police (03) 433-1400, Crimestoppers 0800 555-111.
