Baker said people should be absolutely careful when they're going out, and not go alone to the place where the incidents have occurred.
"Obviously don't go out at night, and if you see anything suspicious or hear anything just contact police."
The most recent assault was reported on August 28, and investigators believe all of these incidents are linked," police said in a statement.
"We acknowledge these incidents rightly cause concern in our community and local police are focused on identifying the person responsible and holding them to account," Kapiti-Mana Area Commander Inspector Tracey Thompson said.
Officers are pursuing "positive lines of inquiry".
"We are asking the public, particularly those on foot alone, to be alert and aware of your surroundings in the area.
"Most importantly if you have information about these incidents, or if you have been a victim of an incident of this nature, we urge you to call us."
Information can be provided to Detective Sergeant Nathan Smith of Kapiti-Mana Police through 105, quoting file number 200829/6042.
Anyone who sees anything suspicious or who has concerns for the immediate safety of themselves or others should call 111 straight away.