Westbrook police are continuing to investigate an incident in which a projectile object struck a school bus Monday.

The bus, carrying children from the Canal School, was struck at around 3:10 p.m. at the intersection of Brackett and Prospect streets.

According to police, witnesses reported seeing a black male hanging out of a green sedan with a firearm at the time of the incident. They also reported seeing two other black males and one white male in the car.

Because the object that struck the bus was not recovered, police say they don’t know what was fired or what kind of firearm was used.

The children were transported to their homes on a different bus, escorted by police.

“Something like that is bound to be unnerving for students,” said Superintendent Stan Sawyer. who believes the incident was a random act.

Sawyer said the school buses are equipped with video cameras, and he watched the tape from the ride. He said the students stood up and were pointing at the window and the car from which the object came.

“I’m just very thankful that no one was harmed,” he said.

Police Chief Bill Baker said the department is following leads and taking witness statements, as their investigation continues.