CARIBOU, Maine — Police are still chasing leads in a Sept. 1 robbery that took place at the McDonald’s Restaurant on Bennett Drive.

Caribou Police Chief Mike Gahagan said Thursday that police have gathered some physical evidence in the case, which remains under investigation.

An employee of the restaurant called police just before 11 p.m. Sept. 1 to report that a person wearing a ski mask had walked up to the drive-thru window and had told the employee that he had a weapon. The employee said the man then demanded that cash from the register be put into a bag and handed over.

The employee complied, according to Gahagan, and the person took off on foot.

The Maine State Police brought in a canine unit and tracked the individual’s scent to Route 89 before it was lost, but physical evidence was recovered and has been sent to the State Police Crime Lab.

Gahagan declined to disclose how much money was taken.

Officers Douglas Bell, Keith Ouellette and Chris Bouchard are investigating the case.