Westbrook police are searching for this man who was photographed at the scene of a fatal collision between a pickup truck and taxi on County Road on Monday morning. This photograph was taken seconds after the collision, and the man left before he could be interviewed as a potential witness. The man isn't suspected in any wrongdoing, police said. Credit: Westbrook Police Department

Westbrook police are searching for a man who may have witnessed a collision on Monday morning that killed three people.

Westbrook police Capt. Sean Lally said a photo taken seconds after a taxi and pickup truck collided on County Road shows an unknown man standing at the the taxi’s driver’s side window. The man left the scene before he could be interviewed, and Lally said police want to talk to him as a potential witness.

The man isn’t suspected in any wrongdoing, Lally said.

Hassan Idris Ali, 39, of Lewiston was driving a 2009 Toyota Camry, registered as a taxi for Orange Taxi and Transportation Service of Portland, west on County Road, also known as Route 22, near the Scarborough town line about 6:52 a.m. Monday when it collided with an eastbound 2014 Nissan Frontier pickup truck driven by Lisa Libby, 60, of Hollis, according to the Westbrook Police Department.

Ali and his two passengers, 50-year-old Gregory E. Harriman of Sebago and 33-year-old Joshua R. Stone of Gorham, were killed in the crash, Westbrook police said.

Libby survived the crash and was taken to Maine Medical Center in Portland, police said.

Anyone who witnessed the crash can contact Officer Brian Grasser of the Westbrook Police Department at 854-644, ext. 2511.