Three people were killed and three others were injured, two critically, when a sightseeing helicopter crashed Saturday morning near Two Harbors on the remote west side of Santa Catalina Island, Los Angeles County sheriff's deputies said.

The helicopter, registered to the sightseeing company Island Express, crashed about 9:30 a.m. near the Little Red Schoolhouse's baseball diamond, a short distance from the town's only hotel, the Banning House Lodge, Deputy Denise Fuchs said.

A witness saw a fireball coming from the exhaust pipe of the helicopter as it flew over the water, sheriff's officials said at an afternoon news conference.

The sky was overcast but there was negligible wind and no rain at the time of the accident, officials said.

Two men and a woman were pronounced dead at the scene, said Los Angeles County Supervising Fire Dispatcher Melanie Flores. They could not immediately be identified, a spokesman from the coroner's office said. Two people with critical injuries were flown to Harbor-UCLA Medical Center in Torrance. Another injured person was taken to County-USC Medical Center in downtown Los Angeles, Flores said.

A woman who answered the phone at the Island Express offices declined to comment.

According to its website, Island Express offers exclusive helicopter tours of Southern California and Santa Catalina Island. The company, whose site says it flies "four top-of-the-line turbine helicopters," was founded in 1982 and operates out of a base near the Queen Mary in Long Beach. It advertises private tours for groups of up to six people and employs three mechanics, according to the website.