The Greenville County Coroner has identified the pilot killed in a jet crash at the Greenville Downtown Airport Thursday.

John Christian Caswell, 49, of Port St. Lucie, Florida, was pronounced dead about an hour after the crash occurred, according to a release from the coroner's office.

Caswell's co-pilot, Stephen George Fox, of Indian Rocks, Florida, also died when the mid-sized jet tried to land at the Greenville Downtown Airport but ran off the runway and split in two, causing a fuel leak that emergency crews rushed to contain.

The reason for the crash was unclear.

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The Coroner's Office said the plane overshot the runway, with the fuselage breaking at the cabin after the jet crashed on Tower Drive. Witnesses said the plane appeared to land without a problem until it overshot the runway and barreled down a steep embankment.

“We all saw it land, and for some reason it did not stop," airport director Joe Frasher said.

The passengers were a married man and woman. They are in critical condition at the hospital, Greenville Fire Department spokesman Tristan Johnson said.

Hospital spokeswoman Sandra Dees said she couldn't share details of the patients' conditions. Frasher said he understood that one of the passengers was in surgery and the other was speaking.

The remaining pilot was still inside the aircraft hours after the crash, with a sheet draped over the cockpit as federal investigators were dispatched from Columbia.

The crash, involving a Dassault Falcon 50 model commonly used in business travel, is the worst in at least 20 years at the airport, Frasher said. The jet was likely landing to pick up more passengers when it ran off a runway embankment and hit nose first, he said.

“In maybe 20 years, we might have had three to four minor incidents and this is probably the most serious,” Frasher said. “We have aircraft this large and larger routinely land at this ramp. It’s very rare that this has happened.”

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The roads near the airport will be closed for some time, Police Chief Ken Miller said.

The fuel leak had been contained to nearby Haywood Road, Fire Chief Steve Kovalcik said. The streams aren't deep in the area, so Kovalcik said "we expect the next good rain we get we'll see more fuel."

Miller encouraged people not to swim downstream, particularly near Haywood Road, nor smoke near the waterway for fear of igniting remnant fuel.

Sam Grice, a flight instructor at the airport who just finished landing from an earlier flight before the crash, said he saw the plane landing, but then looked away and didn't realize it had crashed.

"I feel like it flared, and he just kind of floated a little bit," Grice said. "All of the sudden, right before I walked inside, people were like, 'That jet just ran off the runway.'"

The jet engine was running after it crashed until the gear could be disengaged.

Details from the scene at the airport after the plane crash can be heard in audio captured by LiveATC.net.

Shortly after 1:40 p.m. a man can be heard saying, “As of now, they’re off the runway.”

“I’ve got the Fire Department on the way,” the second voice responds

Then later, a man says, “They are off the runway, they are off the runway in the embankment, the engines are running."

“Are the people on or off the plane? Do you see any people?” another man responds to him.

Then a few minutes later, a man says: "Emergency response is on site."

Kathryn Johnson, of Greenville, lives close to the airport and said she comes to the south ramp often to watch planes take off and land. She said seeing there was a crash is “awful.”

“It’s beautiful. It’s a great airport. You never see anything like this,” she said. “The planes take off here effortlessly.”

The plane is registered to Global Aircraft Acquisitions LLC, based in Delaware. No further information about the company was available through public records.

The crash was the second high-profile wreck involving a plane at the airport within the past two months.

A Beechcraft BE58 belonging to the owner of Halls Chophouse went off the runway and down an embankment during landing on Aug. 3. Everyone on board survived.

Evans said his office was thankful more passengers weren't on the jet during Thursday's crash.

“We’re just lucky that there weren’t any more passengers, souls on the plane," he said. "We’ve only got four to work with and that’s what we’re thankful for.”

The manner of death for the pilots was ruled an accident, the Coroner's Office said. The cause of death for both is pending an investigation.

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