The pilot of a plane which crashed at San Francisco airport, killing two people, may have been temporarily blinded by a bright light as he came into land.

Lee Kang Kuk, who was making his first landing at the airport and had just 43 hours' experience at the controls of the Boeing 777, said he saw a bright flash as he approached the runway.

It happened around 35 seconds before impact when Asiana Airlines flight 214 was around 500ft (150m) off the ground - the point at which the aircraft began to slow down and drop steeply.

Deborah Hersman, who chairs the National Transportation Safety Board (NTSB), said the use of lasers had not been ruled out.

It is not clear whether the flash of light caused the crash or whether other factors were to blame.

The pilot's claim came as phone calls to the emergency services made by passengers on board the plane were released, demonstrating the confusion caused when the Boeing 777 hit the runway.

Pleading for ambulances to be sent, one woman can be heard saying: "There are a lot of people that need help ... We have people over here who weren't found and they're burned really badly."

Meanwhile, it has emerged that passengers were initially told not to evacuate the aircraft.

The plane hit a sea wall as it came into land, causing its tail fin to break off and the rest of the fuselage to spin across the runway.

However, the NTSB found people did not begin leaving the plane until a fire erupted 90 seconds after impact.

"We don't know what the pilots were thinking, though I can tell you in previous accidents there have been crews that don't evacuate, they wait for other vehicles to come to be able to get the passengers out safely," Ms Hersman said.

She suggested that the pilots in the cockpit may not have been in a position to spot the fire outside the plane.

At least one of the emergency escape slides opened inside the aircraft, pinning down two flight attendants.

Three other crew members were flung from the aircraft onto the runway but survived.

The NTSB is using pilot interviews, cockpit recordings and control tower communications to piece together the moments leading up to the crash.

They found both Mr Lee and his co-pilot, Lee Jung Min, who was on his first flight as an instructor , both thought the aircraft's speed was being controlled by an autothrottle, which was set to 157mph.

When they realised the plane was approaching the waterfront runway too low and too slow, they both reached for the throttle.

Passengers heard a loud roar as the pilots made a desperate attempt to abort the landing.

Two Chinese students were killed in the crash, which left 180 people injured. The students, who began their journey to the US in Shanghai, were on their way to a 15 day camp to study English.

Families of around 20 survivors who remain in hospital have begun arriving to care for their loved ones.

Flight 214 was a direct flight from Incheon in South Korea to San Francisco.

A Boeing 777 aircraft has crash-landed at San Francisco international airport, killing at least one person and injuring as many as 30, diplomats say.

Pictures posted on Twitter showed passengers jumping down the inflatable emergency slides and leaving the area, as plumes of smoke rise from the plane.

Firefighters and rescue teams are at the scene of the downed Asiana Airlines Flight 214, which had taken off from South Korea's capital, Seoul.

The cause of the crash is unclear.

Early indications suggest the plane came in too short and hit the seawall at the airport.

Eight adults and two children who suffered critical injuries are being treated at San Francisco General Hospital, hospital spokesperson Rachael Kagan said.

here were 291 passengers and 16 crew on board, Asiana said.

Nationalities on board included 141 Chinese, 77 South Koreans and 61 US citizens, the airline said.

While the sequence of events remains unclear, it appeared the plane landed and then crashed on San Francisco International Airport's Runway 28L, said Federal Aviation Administration spokeswoman Laura Brown.

Footage of the scene showed debris strewn on the runway and smoke pouring from the jet, as fire crews sprayed a white fire retardant into gaping holes in the craft's roof.

One engine and the tail fin appeared to have broken away from the main wreckage.

'Out of control'

Passenger David Eun tweeted a picture of people jumping out of the plane's emergency inflatable slides and wrote: "I just crash landed at SFO. Tail ripped off. Most everyone seems fine. I'm ok. Surreal..."

Mr Eun, who describes himself as a "digital media guy" and "frequent flier", added: "Fire and rescue people all over the place. They're evacuating the injured. Haven't felt this way since 9/11."

A witness to the crash, Ki Siadatan, said the plane "looked out of control" as it descended over San Francisco Bay to land just before 11:30 (18:30 GMT).

"We heard a 'boom' and saw the plane disappear into a cloud of dust and smoke," he told the BBC. "There was then a second explosion."

He saw events unfold from the balcony of his home in the Millbrae area of San Francisco, which overlooks the airport.

Weather conditions were fine and there was little wind, he added.

Arrivals and departures at the airport have been suspended since the incident.

The twin-engine Boeing 777 has a good safety record as a long-haul aircraft and is used by many major carriers.

Asiana is South Korea's second-largest airline.