Halifax Regional Police are looking for a man who's been going door-to-door in recent weeks asking Dartmouth residents about home alarms and trying to sell the systems.
Police say his suspicious behaviour escalated Thursday when he asked a 17-year-old girl at a home on Topsail Boulevard to go for a drive.
When the girl refused, it's alleged the man tried to grab her arm and pull her outside.
She closed the door and called police.
Police describe the suspect as a white man between 20 and 30 years old with light brown hair.
He was wearing a black hoodie, blue jeans and sneakers.