The plane, bound for Dallas from New York’s LaGuardia airport, landed shortly after 11 a.m. on Tuesday at Philadelphia International Airport. Seven people suffered minor injuries, and one was critically injured and later died.

The dead passenger was not identified but other passengers reported a woman being severely injured during the flight receiving aid from other passengers in a chaotic and bloody scene.

The cabin suddenly lost pressure when engine debris pierced the window and flight attendants were crying, one passenger, Marty Martinez, founder and chief executive officer of Social Revolt digital marketing in Dallas, said in an interview.

“When we saw that they started crying, of course we thought we were in a really bad place. We were going down,” Martinez said. The woman who was injured “made no noise at all,” he said.

The death is the first fatality on a U.S. passenger airline in more than nine years, said National Transportation Safety Board Chairman Robert Sumwalt at a press conference.

The last fatal accident on a U.S.-registered carrier occurred near Buffalo, New York, on Feb. 12, 2009, when a commuter carrier operated by Colgan Air crashed, killing 49 on board and a man on the ground.

Television feeds and photos posted on Twitter show the front of the left engine on the Boeing Co. 737-700 was ripped open.

The Federal Aviation Administration halted some arrivals and departures at the Philadelphia airport but reopened it shortly before 2 p.m., according to an agency website. The crew of the plane reported that it suffered damage to its fuselage and at least one window, according to the FAA.

The plane had been aloft for about 30 minutes when an explosion shattered the routine and oxygen masks descended from the ceiling, Martinez said. He and others took to social media, using the plane’s Wi-Fi connection, trying to leave final messages in case the plane crashed.

“I kind of just felt like it was over,” he said. “We’re flying at 30,000 feet going 500 miles an hour.”

Reports of shrapnel shattering a window suggest that the engine broke apart in what is known as an “uncontained” failure. U.S. regulations require engines to be covered in tough casings designed to prevent metal from flying into fuel tanks and passenger areas if an engine breaks apart.

CFM Engine

The plane in Tuesday’s emergency was powered by CFM56-7B engines, which are made by CFM International Inc., a joint venture between General Electric Co. and France’s Safran SA. CFM, the sole supplier of engines for 737-700 planes, said it has sent technical representatives to examine the plane.

The CFM engines are among the most widely used in the world, powering more than 6,700 aircraft for more than 350 million flight hours, CFM said in a statement.

The NTSB said in a tweet it was sending a team to investigate. The NTSB investigates the most serious engine failures and conducted a probe of a similar Southwest incident in 2016 involving the same type of engine.

In that incident, a fan blade snapped off a Southwest 737-700 engine mid-flight, sending debris slamming into the plane and damaging the fuselage, wing and tail. Investigators with the NTSB later found evidence of a crack consistent with metal fatigue on the titanium-alloy blade. No one on the plane was hurt.

Earlier: Southwest Engine Fan Blade Broke off Mid-Flight Last Month

While engine failures haven’t caused a major crash in the U.S. in decades, incidents that threaten safety continue to occur.

On Oct. 28, 2016, an engine on an American Airlines plane exploded on a Chicago runway as it was preparing to take off, triggering a massive blaze that melted one wing. A disk within the GE CF6-80 engine was later found to have a manufacturing defect, the NTSB said. Pieces of the spinning disk flew as far as 2,920 feet (890 meters), striking a warehouse. Theplane was a Boeing 767.

The 737-700 was delivered in August 2000 and only flown by Southwest, FAA records show. The model is the smallest jetliner currently manufactured by Boeing and is the heart of the airline’s all-737 fleet. The Texas carrier has hunted for used -700s in recent years as it parked an earlier version known as the 737 Classics.

Meanwhile, in an unrelated incident Tuesday, a Delta Connection flight from New York’s LaGuardia Airport diverted to Washington Dulles International Airport after experiencing an issue with the plane’s wheel.

A pilot for regional affiliate ExpressJet Airlines had just lifted off shortly before 11 a.m. when a wheel on the Bombardier CRJ700 had an unspecified problem, Delta spokesman Michael Thomas said. The pilot elected to land at the Washington-area airport instead of continuing on to its destination at Richmond, Virginia. The flight landed safely and without incident, an ExpressJet spokesman said.