An airplane sits on the ground after crash landing at Penmar Golf Course in Venice, Los Angeles on Thursday. Actor Harrison Ford was seriously injured when he crashed his vintage plane shortly after taking off from a local airport.

Reuters/Los Angeles

Star Wars star Harrison Ford was seriously injured on Thursday when the actor crashed his vintage plane on a Los Angeles golf course shortly after taking off from a local airport, a source told Reuters.

The single-engine plane clipped a tree as it went down shortly after taking off from Santa Monica Airport, about a mile (1.6 km) away, and the pilot survived in "fair to moderate" condition, Assistant Los Angeles Fire Chief Patrick Butler said.

Butler declined to confirm that Ford was on board the aircraft, but a source close to the investigation said it was the 72-year-old actor.

"At the hospital. Dad is OK. Battered but ok!" Ford's son, Ben, said on Twitter. "He is every bit the man you would think he is. He is an incredibly strong man."

A Los Angeles Police Department spokeswoman said the cause of the 2.25 pm crash appeared to be mechanical failure.

Butler said the pilot was conscious and breathing following the accident and was initially tended to by bystanders before paramedics responded and transported him to a local hospital.

Paramedics "initiated spinal immobilisation, started an IV and began all the necessary medical protocols that we do," Butler said.

Aviation enthusiast

Celebrity website TMZ reported that Ford suffered multiple gashes to his head and was bleeding profusely. Representatives for Ford could not immediately be reached for comment.

The actor, best known as archaeological adventurer Indiana Jones in Raiders of the Lost Ark and its sequels and as the space hero Han Solo in the Star Wars series, is a longtime aviation enthusiast.

Carlos Lugo, 63, said he was playing golf at the Penmar Golf Course when he saw a plane that he believed had taken off from nearby Santa Monica Airport lose power and turn around in an apparent attempt to return to the runway.

"When he flew over us we knew it was too late to make it back to the airport," Lugo said.

The Ryan Aeronautical plane involved in the crash was built in 1942 and registered to the company MG Aviation Inc, according to FAA online records.

In 1999, Ford and a flight instructor went down in a helicopter crash north of Los Angeles, and the helicopter also was registered to MG Aviation, according to a Los Angeles Times report at the time.

Ford suffered a broken leg last year while filming on the set of Disney's Star Wars: Episode VII set in England, in which he is reprising his role as Han Solo. Production on the movie was halted for two weeks as he recovered.

The National Transportation Safety Board said in a tweet that it would investigate the accident.