Police shot and killed a man Tuesday night onboard a coach bus stopped in Norwalk, Connecticut, after he had stabbed two passengers with a box-cutter.

The Dahlia Travel and Tours bus, based out of Queens, New York, was carrying around 24 people to a casino around 10 p.m. when a man with a "cutting instrument" had an altercation with other passengers. He then stabbed a man and woman riding on the bus, as well as himself.

Several passengers called 911 as they drove along busy Northbound I-95. Before authorities could catch up to them, the bus driver pulled into a construction zone and quickly flagged down a nearby police officer at 10:15 p.m. The bus was shut down along I-95 as police responded to the stabbing incident.

When officials arrived, one police officer said the assailant and a passenger were seen fighting and fell out of the parked bus onto the pavement. When the suspect was told to drop the weapon, he did not stop and even came toward the trooper with the box-cutter.

According to reports, the trooper then shot the armed man and a witness was grazed by the bullet. However, the bullet did not seriously injure the witness but it is unclear if the bullet struck both attacker and victim or if it ricocheted off the pavement before striking the witness.

The three injured passengers and attacker were all given medical care at the scene before being sent to the hospital, where the man and his two stabbing victims later died. The police trooper was evaluated for injuries but was unharmed in the attack.

Unharmed passengers were held on the bus for close to three hours before they were allowed to disembark. The exits blocked on I-95 during the investigation were reopened around 5:30 a.m. Wednesday.