The pilot tried to abort the landing 1.5 seconds before crash.

SAN FRANCISCO — Asiana Airlines says the pilot of the ill-fated Boeing 777 that crashed here Saturday had little experience flying the aircraft and was landing one for the first time at San Francisco International when it slammed into the runway, killing two teenaged passengers and injuring more than half the 307 passengers and crew.

Airlines spokeswoman Lee Hyomin said Monday that Lee Gang-guk, who was at the controls of Saturday's nearly 10 1/2 hour flight from Seoul as it arrived at SFO, had nearly 10,000 hours flying other planes but only 43 in the 777, a plane she said he still was getting used to flying.

Separately, San Francisco Fire Chief Joanne Hayes-White said it was "a possibility" that one of the teens was killed on the tarmac by a vehicle driven by one of the first-responders at the scene. San Mateo County coroner Robert Foucrault said an autopsy was expected to be completed Monday.

Tom Siragusa, an assistant fire department chief described a harrowing search and rescue operation by firefighters and other first-responders, who twice entered the smoke-filled, burning aircraft to search for survivors while navigating crash debris and leaking jet fuel. The top priority was getting people off the plane, Siragusa said. "Everyone rose to the occasion and I couldn't be prouder of everyone in my department."

"It just seemed to be surreal, like it wasn't happening," said Lt. Dave Monteverdia, who he said rescuers' "only way up" to reach the victims was via the plane's emergency chutes deployed after the crash.

Gang-guk had flown Boeing 747 jets into San Francisco International previously, according to an airline spokeswoman, and was assisted on this flight by deputy pilot, Lee Jeong-min. South Korean transport official said the deputy had about 12,390 hours of flying experience, including 3,220 on the 777.

Two other pilots were aboard the plane, rotating at the controls during the long flight.

South Korea and U.S investigators have wrapped up interviews with the four pilots. But Korean officials say pinpointing an exact cause of the crash may take months, or years. "We cannot conclude the accident was caused by a pilot mistake. Whether there was a pilot mistake can be confirmed after all related data are analyzed and inspected," said Choi Jeong-ho, the head of South Korea's transport ministry aviation policy bureau.

National Transportation Safety Board Chairman Deborah Hersman said Sunday that Flight 214 was traveling far below its target speed for landing when it crashed short of the runway Saturday. "The speed was significantly below 137 knots, and we're not talking a few knots," she said.

The initial impact ripped the plane's tail section off, coming to rest hundreds of feet from the main body of the aircraft, which burst into flames.

It was the first fatal crash of a commercial airline in the USA since February 2009. But remarkably, all but two of the 291 passengers and 16 crew survived and more than a third required hospitalization. At least 168 people were treated for injuries. Eight remained in critical condition Monday.

The flight, which originated in Shanghai before stopping in Seoul en route to San Francisco, carried 61 U.S. citizens, 77 South Koreans and 141 Chinese.

Hersman said investigators will look at all possibilities for the cause of the crash, including pilot error. "Everything is on the table," she said.

She provided details of what investigators found in their initial review of the plane's flight data and cockpit voice recorders: "The approach proceeds normally as they descend. There is no discussion of any aircraft anomalies or concerns with the approach. A call from one of the crewmembers to increase speed was made approximately seven seconds prior to impact."

The "stick shaker," which gives an audible and motion signal warning that the plane is flying too slowly and is about to stall, sounds "approximately four seconds prior to impact."

The pilot requested a "go-around" — to abort the landing, fly around the airport and try again, Hersman said.

"A call to initiate a go-around occurred 1.5 seconds before impact," she said.

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Cabin manager Lee Yoon-hye, 40, said she has nearly 20 years' experience with Asiana and knew seconds before impact that something was wrong with the plane.

"Right before touchdown, I felt like the plane was trying to take off. I was thinking, 'What's happening?' and then I felt a bang," Lee said. "That bang felt harder than a normal landing. It was a very big shock. Afterward, there was another shock and the plane swayed to the right and to the left."

Lee, who was apparently the last person to leave the burning plane, said crewmembers deflated the slides with axes to rescue their colleagues, one of whom seemed to be choking beneath the weight of a slide.

One flight attendant put a scared elementary schoolboy on her back and slid down a slide,Lee said. A pilot helped another injured flight attendant off the plane after passengers escaped.

Lee, who suffered a broken tailbone, told reporters she worked to put out fires and usher passengers to safety in the harrowing moments after the plane went down.

Lee said she tried to approach the back of the aircraft before she left to doublecheck that no one was left inside. But a cloud of black, toxic smoke made it impossible. "It looked like the ceiling had fallen down," she said.

The two teen girls who died are Ye Mengyuan and Wang Linjia, from China's eastern Zhejiang province, according to China Central TV. They were among a group of 29 middle-school students and five teachers heading for a summer camp in the USA. Their bodies were found outside the plane, which had come to rest between runways.

They were headed to a three-week stay in Los Angeles at a church school in the San Fernando Valley, West Valley Christian School administrator Derek Swales said.

Vedpal Singh, who was sitting in the middle of the aircraft and survived the crash with his family, said there was no warning from the pilot or any crewmembers before the plane touched down hard and he heard a loud sound.

"We knew something was horrible wrong," said Singh, who suffered a fractured collarbone and had his arm in a sling. "It's miraculous we survived."

Passenger Benjamin Levy, 39, said it looked to him as though the plane was flying too low and too close to the bay as it approached the runway. Levy, who was sitting in an emergency exit row, said he felt the pilot try to lift the jet up before it crashed and thinks the maneuver might have saved some lives.

"Everybody was screaming. I was trying to usher them out," he recalled of the first seconds after the landing. "I said, 'Stay calm, stop screaming, help each other out, don't push.' "

Welch reported from Los Angeles and Stanglin from McLean, Va. Contributing: Calum MacLeod in Beijing, Nancy Blair and Scott Martin in San Francisco, and Nancy Blair, USA TODAY; Associated Press