An Alaska Airlines jet has crashed in the ocean near Los Angeles. The plane, reported to be a Boeing MD-80, was headed to San Francisco then Seattle from Puerto Vallarta.

It is believed there were 83 passengers and five crew members -- two pilots, three flight attendants -- on board Flight 261. The crash occurrred at 4:15 p.m. local time.

There isn't much hope that anyone survived the crash, as the fuselage could be seen about 30 metres under the water upside-down. A witness says the plane actually hit the water upside-down.

Helicopters were in the air over the ocean, with Coast Guard boats searching for survivors and wreckage. A U.S. Coast Guard spokesperson said several bodies have been recovered from the water.

The crash site is off Point Magu, 30 kilometres northwest of Los Angeles, near the beach resort of Malibu.

Debris and oil slicks could be seen floating on the ocean surface.

Alaska Airlines customer service agent Len Sloper says the pilot reported problems with the "stabilizer trim." This might mean they were having a hard time bringing the plane into the proper pitch up or down.

The plane requested permission to land at Los Angeles.

An MD-80 can carry about 150 passengers.

An emergency number has been provided for people who believe they may have had family members aboard the flight.

The number is 1-800-553-5117.