A porn actor who plunged to his death off a cliff as police tried to arrest him for murder and attempted murder after a sword rampage, aimed to kill or maim as many people as possible a detective said.

Stephen Hill was "hell-bent" on taking lives and was indiscriminate about his victims, Joel Price said.

Hill fell to his death on Saturday after officers trapped him on a hillside cliff overlooking Los Angeles' San Fernando Valley.

Mr Price said officers believe Hill jumped rather than fell after they tried to take him into custody following a nine-hour stand-off. Police said the actor, armed with the sword he used in the June 1 attack, had repeatedly threatened suicide.

News video shows Hill, still holding the sword, tumbling off the cliff after sliding to its edge from a seated position. Several officers had moved to almost within reach of him.

Earlier, police said he went over the cliff after a "less than lethal munition" was fired at him. They did not say whether the projectile struck him.

"Everyone out there would have wished for a different outcome," Mr Price said. But he said officers had to try to take Hill into custody after failing to persuade him to surrender.

Hill's death came just four days after he went on a rampage at Ultima DVD's production facility in the San Fernando Valley. He fatally stabbed one Ultima employee, Herbert Hin Wong, 30, and wounded two others, Christopher Rachal, 36, and Yuri Drell, 28.

"He was hell-bent on hurting, killing as many people as he could," Mr Price said.

Hill, 34, had worked both as an actor and in production for Ultima, a small company that produces niche films featuring fetishes and sexual domination of men.

He had been living on a film set at the production unit but was recently sacked and ordered to move out.

On Friday, the district attorney's office charged him with one count of murder and five counts of attempted murder for the attacks, which occurred during a small social gathering at the unit.

Police said Hill fled to the San Fernando Valley hillside after officers found him hiding in a nearby house in the valley's West Hills neighbourhood.

Hill, who acted under the name Steve Driver, is credited with 13 films on the Internet Adult Film Database.