Boeing 777 crash lands at San Francisco airport

An Asiana Airlines Boeing 777 crashed while landing at San Francisco International Airport Saturday local time.

Two people were killed and 180 injured.

Asiana Airlines - a South Korean carrier - says the flight carried 291 passengers and 16 crew members.

There was no immediate indication of the cause of the crash. The plane landed short of the runway; some eye witness reports have it hitting a sea wall. The tail snapped off as the rear of the plane hit the ground first, then landing gear and one engine were ripped off as it spun before coming to rest in an area off the runway (see a diagram of the landing here; a CNN video of the actual crash here).

An navigation system at the airport called Glide Path, which helps guide in pilots during bad weather, was switched off at the time of the crash, leaving the pilots to operate by visual cues alone.

Korean American David Eun (@Eunner) was onboard and tweeted the aftermath of the crash.

"I just crash landed at SFO. Tail ripped off. Most everyone seems fine. I'm ok. Surreal... " Mr Eun tweeted at 7.15am Sunday morning NZ time.

One engine was ripped off, but both wings remained intact. Images show substantial damage to the top of the plane, and large sections of its roof missing.

Video posted to YouTube (below) and KTVU images show extensive fire damage to plane, but also passengers escaping via emergency inflatable slides.

Mr Eun is reportedly an executive vice president at Samsung. He tweeted that he did not want to draw attention from the crash, but did want to let people know everybody was okay.

He added, "Fire and rescue people all over the place. They're evacuating the injured. Haven't felt this way since 9/11."

Another tweeter, Stefanie Laine (@stefanielaine) took a long distance photo of the crash as it happened. The photo was taken from her hotel across the water. She tweeted the planed seemed to "Came in at a bad angle, flipped, rolled, broke apart."