5 Charged in Death of Honor Student : Crime: Prosecutors say 18-year-old masterminded the brutal slaying of Stuart A. Tay and could face death penalty. Four other teen-agers face murder counts.

Prosecutors alleged Wednesday that an 18-year-old high school honor student was the mastermind behind the gruesome slaying of fellow senior Stuart A. Tay and said the young man could face the death penalty for his role in the murder.

On Wednesday, prosecutors added the special circumstance of “lying in wait” to the murder charge against Robert Chan. Chan is accused of orchestrating the New Year’s Eve slaying of 17-year-old Tay, who like Chan, was an outstanding student and computer whiz.

Four juveniles also have been charged with murder. Prosecutors intend to try them as adults because of the brutal and premeditated nature of the slaying.

Police and prosecutors said the suspects, students at Sunny Hills High School in Fullerton, rehearsed their roles before the murder and dug Tay’s grave a full day before the crime.

Tay, a senior at Foothill High School in Santa Ana, met his alleged killers in the garage of the Buena Park home where one suspect lives. Police said Tay had gone there to pick up a gun to be used in a scheme to steal computer parts from an Anaheim distributor.

As he bent over to examine the gun, Tay was repeatedly beaten with a baseball bat and sledgehammer, police said. While he was still breathing, Tay’s mouth was forced open and rubbing alcohol was poured down his throat, police said. His mouth was then covered with duct tape. Police said he asphyxiated in his vomit.

He was buried in a shallow grave under a rubber tree. Later that night, some of the suspects went to a New Year’s Eve party in Irvine, said Dep. Dist. Atty. Lew Rosenblum.

“It’s very bizarre and it’s very frightening to see that children with such good backgrounds, from strong families, would be willing to partake in these type of activities,” Deputy Dist. Atty. Lew Rosenblum said Wednesday. “It’s very disturbing.”

The suspects in the Tay case were more accustomed to finding their names on the honor roll than on a police blotter.

According to an acquaintance, Chan was tied with another student to become Sunny Hills valedictorian. Charles Choe, 17, of Fullerton, was a volunteer in the child-care section of a local YMCA. Kirn Young Kim, 16, of Fullerton, is a doctor’s son.

Also charged with murder are Mun Bong Kang, 17, of Fullerton and Abraham Acosta, 16, of Buena Park.

Choe, Kang and Kim entered not guilty pleas Wednesday in Orange County Juvenile Court and were ordered to return Feb. 5 for a hearing to determine whether they should be tried as adults. Acosta’s arraignment was continued because his attorney was not present.

The teen-agers stared at the floor as their parents looked on, many of them sobbing and unable to make sense of what has happened.

“I’m still finding out what’s going on,” said Choe’s mother, who declined to give her first name. “I don’t know. He was a good boy. Never in trouble.”

She said her son had applied to several University of California campuses and had scored extremely high on his Scholastic Aptitude Test. She quoted him Wednesday as saying, “I can’t get a job. My life is messed up.”

Kirn Kim’s aunt, Kris Lee, who attended the court hearing with Kim’s parents, described her nephew as “a very, very nice kid.”

“It was something where he was in the wrong place at the wrong time,” she said. “All teen-agers are exposed to that. We watch them 24 hours a day and stuff still happens.

“I think he was a victim, too.”

Police say Tay was killed after a plot to steal computer parts from an Anaheim distributor went awry. Investigators said his accomplices killed Tay after they learned he had been using a fictitious name and concluded that they could not trust him.

Prosecutor Rosenblum said Chan was the mastermind of Tay’s murder. “He appears to be the one who set the plan in motion,” he said.

Chan’s arraignment on Wednesday was postponed.

Browne said Tay and the five suspects had apparently bought computer parts together before. The suspects would not tell investigators when they had allegedly planned to rob an Anaheim distributor of computer parts, Browne said.

According to a police affidavit filed Monday, Chan was also angry with Tay “because of the poor planning Tay had made” for the robbery, according to a police affidavit filed Monday.

Times staff writer Matt Lait contributed to this story.