A bus carrying more than 40 passengers, mostly high school students returning from a spring break trip to Europe, struck a bridge overpass Sunday night on a Long Island parkway where commercial vehicles are prohibited because of low-clearance bridges.

Images from the scene show the roof of the white bus sheared off. Police said it was a high-impact crash that sent the bus all the way through the overpass and out the other side.

“We’re very lucky,” said Maj. David Candelaria of the New York State Police. “This could’ve been tragic.”

The crash occurred shortly after 9 p.m. Eastern time on the Southern State Parkway at Eagle Avenue. Six people were seriously injured and 37 suffered lesser injuries such as cuts and bruises, Candelaria said at a news conference. He estimated the height of the clearance to be less than 10 feet.

The bus was transporting 38 students, ages 16 to 18, and five adult chaperons from John F. Kennedy International Airport to a mall where parents were waiting to pick their children up, Candelaria said.

One person sustained very serious injuries, which included broken bones and soft tissue injuries, officials said. Most passengers exited the bus on their own, but Candelaria said some had to be extricated from the wreckage. Those with injuries were taken to five local hospitals, he said.

Candelaria said the crash was treated as a “mass casualty incident,” adding that more than 10 ambulance companies from around Nassau County responded to the scene. “They set up a mass casualty treatment triage and probably saved lives,” he said.

Video footage from the scene showed empty stretchers and first responders surrounding the front of the bus as red lights from multiple emergency vehicles reflected off the bus’s white exterior. The bus was stopped between the right lane and the road’s shoulder. Seats were visible where windows used to be. Glass and debris littered the road, and passengers could be seen along the grassy shoulder huddled in groups or pacing aimlessly.

The bus driver is not from the Long Island area and may not have known that commercial vehicles are not allowed on the parkway, Candelaria said. The bus is owned by Journey Bus Lines, a New Jersey-based company, he said.

“I don’t think he had any awareness because if you look at the damage, it’s a high-impact strike,” he said, adding that the incident remains under investigation.

This is not the first time an oversize vehicle has struck the Eagle Avenue bridge.

With a height of just under 8 feet, the overpass “has one of the lowest clearances of any bridge on any Long Island parkway,” the Baldwin Herald reported in 2015. It is struck from beneath by tall vehicles an average of three times per year, according to the news site.

In December, Gov. Andrew M. Cuomo announced a $4.3 million project to install an electronic warning system that detects when oversize  vehicles enter parkways. “New York State parkways traditionally have bridges that are lower than the standard legal bridge clearance,” a statement from the governor’s office said.

Detectors were to be positioned at the  top of ramps and “relay an invisible beam that is set at a specific bridge clearance height for the area, the statement said. When an oversize vehicle tripped the sensor, it would trigger a warning message on a full-color LED sign display that alerts the driver of imminent bridge strikes. The system would also send an alert to the state’s Department of Transportation, which would then notify state police, according to the Baldwin Herald.

“The impact to the overpass was significant,” Candelaria said after Sunday’s bus crash. “It wasn’t just a bump. If you look at the bus from the side, it’s got substantial damage.”

The scene after a bus carrying more than 40 passengers struck a bridge overpass

A bus that was carrying teenage passengers sits on the side of a highway after it hit an overpass on the Southern State Parkway in Lakeview, N.Y., Monday, April 9, 2018. The charter bus carrying teenagers returning from a spring break trip struck a bridge overpass on Long island, seriously injuring several passengers and mangling the entire length of the top of the bus. (AP Photo/Kevin Hagen)

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