PORTLAND – Police are investigating a wave of armed robberies in Portland and South Portland and suggesting they are likely the work of one man.

During the past week, a man displaying a gun or warning that he had one held up five businesses, including two hotels, a video store, a fast-food restaurant and a natural-foods market.

Armed robberies are uncommon in the area, and Portland Police Chief Michael Chitwood said he believes that the same gunman carried out all five holdups.

“We have seen an escalation in the last couple days that is frightening. It’s almost like this guy is losing control,” Chitwood said. “My fear is that a member of the community could be hurt if they resist.”

Police believe the robber lives locally, drives a car and may be stealing to support a drug habit. They are cautioning store clerks not to try to chase the gunman but to call police after he has left the premises.

The robberies netted several hundred dollars.