Three young women have pleaded guilty to voluntary manslaughter for luring a man to an isolated area near the ocean in San Francisco, shooting him in the head and stealing his car and wallet, authorities said Wednesday.

Kimberly Gutierrez, 21, of San Francisco, pleaded guilty Friday and faces up to 21 years in prison for her role in the killing of Eugene Gorenman, 27, of San Francisco, who was found dead near a gun battery at Fort Funston on March 29, 2004.

Gutierrez was 16 at the time. She had been charged as an adult with murder, and could have been sentenced to 25 years to life if convicted.

A co-defendant, Felicia Mehrara, 21, was also a juvenile at the time of the killing. She and another co-defendant, Jillian McIlvenna, 24, also pleaded guilty to manslaughter rather than be tried for murder. McIlvenna faces 10 years in prison and Mehrara faces eight years when the women are sentenced April 3 in San Francisco Superior Court.

Erica Derryck, spokeswoman for the district attorney's office, said the only witnesses to the crime were the perpetrators. "We believe this disposition ensured the toughest sentence," she said.

Gorenman was a Russian immigrant who grew up in Walnut Creek, graduated from UC Berkeley and worked as a computer engineer with Pacific Gas and Electric Co.

Police homicide investigators focused on the three women after one of Gorenman's credit cards was used to buy a cell phone after he was found dead.

The buyer said he had stolen the card from three girls he met in downtown San Francisco. He led police to a house in San Bruno where McIlvenna and Gutierrez were living together.

McIlvenna eventually told police that she and her friends had been targeting men - striking up conversations with them with the goal of getting their cash and property.

McIlvenna told authorities that she and three other teenage girls had enticed Gorenman to Fort Funston after he pulled up alongside them at a traffic light on Fulton Street. One of the four girls was never charged.

As the girls walked with him near a World War II bunker, Gutierrez shot Gorenman in the head, and Mehrara took his wallet, McIlvenna told authorities.

Gutierrez then drove away in Gorenman's car, took off the license plates and abandoned it in the Bayview district, McIlvenna said.

After the killing, the defendants had a falling out and eventually McIlvenna agreed to testify.

Gutierrez's attorney, Tony Tamburello, said the killing was "a tragic event, and the three young women - two of them were minors at the time - are taking responsibility for it."

"It's difficult to understand why and how it happened," Tamburello said. "But they are taking responsibility - that's the bottom line."