One person has been killed and seven others needed medical treatment after an engine on a US passenger jet apparently exploded in midair.
Southwest Airlines Flight 1380 made an emergency landing in Philadelphia after a window, wings and fuselage were damaged in the incident, officials say.
In an air traffic control recording, one of the pilots can be heard saying "there is a hole and someone went out".
The last passenger death on a US commercial flight was in 2009.
The Boeing 737-700 had been en route from New York's La Guardia airport to Dallas, Texas, with 143 passengers and five crew when the incident happened on Tuesday morning.
Witnesses say a woman was sucked out of the window but pulled back in by other passengers.
The plane made a safe landing at 11:20 (15:20 GMT), fire officials said.
In the air traffic control recording released by NBC News, pilot Tammie Jo Shults is heard saying: "We have a part of the aircraft missing, so we're going to need to slow down a bit."
Asked if the plane is on fire, she says it is not but adds: "They said there is a hole and someone went out."
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The father of one passenger on board the plane told NBC Philadelphia that a woman was "partially sucked out" of a window after it was pierced by debris from the engine.
She was pulled back inside by other passengers, Todd Bauer added.
The US Federal Aviation Administration has opened an investigation.
The National Transportation Safety Board (NTSB) said they were aware of one fatality in the suspected "engine failure".
NTSB Chairman Robert Sumwalt told reporters the type of engine, a CFM56, is "very widely used in commercial transport".
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Joe Marcus@joeasaprap
What a flight! Made it!! Still here!! #southwest #flight1380
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The Philadelphia Fire Department said one passenger had been taken to hospital in a critical condition while seven other people were treated for minor injuries at the scene.
In a statement, Southwest Airlines said it was "devastated" and extended sympathy to all those affected by the "tragic event".
Philadelphia Fire Commissioner Adam Thiel told a news conference that passengers and crew "did some pretty amazing things under very difficult circumstances".
First responders "found a fuel leak and small fire in one of the engines", he said, adding that they used foam to extinguish the flames.
'Blood everywhere'
Images have been shared on social media showing passengers sitting in oxygen masks as the plane shudders around them.
"All of a sudden, we heard this loud bang, rattling..." said one passenger.
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Kristopher Johnson@EMMS_MrJohnson
@SouthwestAir These are the hero’s of SWA 1380 NYC to Dallas We lost an engine mid-flight and they guided back to Philly saved 149 on board
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"It just shredded the left-side engine completely... it was scary," Kristopher Johnson told CNN.
Timothy Bourman, a pastor from New York City, told he had been sitting in the rear of the plane when he heard a loud boom.
"All the sudden, it felt like we dropped 100 feet," he said.
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Matt Tranchin@mtranchin
If this ends up being the opening scene to Final Destination 13, I'm going to be really salty. #Flight1380
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">https://twitter.com/mtranchin/status/986279898183622657" class="off-screen" tabindex="-1">End of Twitter post by @mtranchin— (@mtranchin) End of Twitter post by @mtranchin">"We were kind of out of control for a while. It seemed like the pilot was having a hard time controlling the plane. Honestly I think we just all thought we were going down."
When flight attendants told passengers to brace for impact, Mr Bourman said he and his wife worried for the worst.
"We're just all really thankful to be alive right now," he said. "Thankful to God, thankful to that pilot."
Passenger Marty Martinez posted a brief Facebook live with the caption: "Something is wrong with our plane! It appears we are going down! Emergency landing!! Southwest flight from NYC to Dallas!!"
After landing, he told CBS News that it felt like the plane was "free-falling", and added that he saw one injured woman being taken off the plane by rescuers.
"There was blood everywhere," he said.
"First there was an explosion and then almost immediately the oxygen masks came down and probably within a matter of 10 seconds the engine hit a window and busted it wide open."
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