The revelations are the latest in a flurry of developments from the crash at San Francisco International Airport that killed two 16 year-old girls from China and sent 182 people to the hospital Saturday.
The flight, with 307 people on board, originated in Shanghai, China, and stopped in Seoul, South Korea. It was preparing to land in San Francisco when the rear of the plane struck the edge of the runway, severing the tail and causing the plane to erupt in smoke and flames.
Questions surround tragedy
The San Francisco Fire Department said one of the girls killed may have been struck by an emergency vehicle, San Mateo County Coroner Robert Foucrault said.
"Part of our examination is to determine the cause of death. Our examination will determine whether it was from the airplane crash or secondary incident," Foucrault said.
Ye Mengyuan and Wang Linjia were among 35 Chinese students headed to California to attend West Valley Christian School's summer church camp, the school said on its website.
The two girls had signed up for the $5,000 summer program aimed to improve students' English.
The National Transportation Safety Board is also looking into reports that one of the girls may have been run over by an emergency vehicle.
"We are aware of the reports but don't have any details yet," NTSB spokeswoman Kelly Nantel said. "Our investigators will be looking very closely at this issue ... We are looking to determine if there are lessons to be learned from this accident."
The San Francisco Fire Department has not responded to CNN's request for comment.
Pilot's flight record
The pilot who was landing Asiana Airlines Flight 214 was making his first descent with a Boeing 777 at the San Francisco airport, the airline said.
But it wasn't his first time flying to San Francisco nor his first time in control of a 777.
Lee Kang-kuk, the pilot who was in the captain's seat, had flown from Seoul to San Francisco several times between 1999 and 2004, the airline said.
Including the flight Saturday, Lee flew a Boeing 777 nine times, clocking a total of 43 hours on that model of aircraft, Asiana said. He has piloted a total of about 10,000 hours, the airline said.
Lee was one of four pilots on board who were working in shifts Saturday. All four pilots have been interviewed by NTSB and South Korean investigators, said Choi Jeong-ho, the head of South Korean's Aviation Policy Bureau.
"We cannot reveal what's been said as it is an on-going investigation," Choi said.
Clues from the voice recorder
The cockpit voice and flight data recorders showed the flight was coming in too slow and too low and that the pilots apparently sped up seven seconds before impact, the National Transportation Safety Board said Sunday.
Four seconds before impact, a stall warning sounded -- warning the pilots the plane was about to lose its ability to stay in the air.
The voice recorder apparently showed the pilots tried to abort the landing less than two seconds before the plane crashed, NTSB head Deborah Hersman said.
The crew then made an internal decision "to initiate a go-around 1.5 seconds to impact," she said.
When asked if pilot error was to blame, Hersman said the crash landing was still under investigation.
"I would discourage anyone from drawing any conclusions at this point," she said.
The NTSB has ruled out weather as a problem and said that conditions were right for a "visual landing."
Officials are investigating whether construction at the airport may have played a role.
Construction to extend a runway safety area temporarily shut off the so-called glide slope system, which is one of several options pilots have to help them land planes safely, Hersman said.
The frightening crash
With no warning from the cockpit, survivors said, the plane slammed onto the edge of the runway near the seawall. The impact severed the plane's tail and sent the rest of the body spinning on its belly.
When rescuers arrived, they found some passengers coming out of the water, said city fire chief Joanne Hayes-White.
"There was a fire on the plane, so the assumption might be that they went near the water's edge, which is very shallow, to maybe douse themselves with water," she said.
Amateur video obtained exclusively by CNN shows the plane crashing and spinning counterclockwise and coming to a stop. Fred Hayes said he shot the video about a mile from the crash scene.
In all, 182 people were hospitalized. Their injuries ranged from severe road rash to paralysis.
The crash, followed by flames and clouds of smoke spewing from the gaping roof, left many fearing the worst.
But 123 of the 307 people on board walked away uninjured.
"We're lucky there hasn't been a greater loss of life," the fire chief said.
Medical personnel were also expecting more casualties.
"We were expecting a lot of burns, but we didn't see them," said Dr. Margaret Knudson, San Francisco General Hospital's chief of surgery. Six survivors were in critical condition at the hospital Sunday.
Many of the injured said they were sitting toward the rear of the aircraft, said Knudson. Several suffered abdominal injuries and spine fractures, some of which include paralysis and head trauma, she said.
Passenger Benjamin Levy said he was bracing for more trauma but ended up walking away from the wreck.
"Honestly, I was waiting for the plane to ... start flipping upside down, in which case I think a lot of people would have not made it," Levy said.
"If we flipped, none of us would be here to talk about it."