``We thought he was joking,'' said Neil O'Grady, 15. ``We were, like, `Yeah, right.''' While they didn't want to warn authorities, he said, friends did check ``Andy'' Williams for weapons Monday morning, but didn't search his backpack.

Authorities said Charles Andrew Williams opened fire at Santana High School, killing two and injuring 13 in this middle-class San Diego suburb. The gun belongs to the boy's father, District Attorney Paul Pfingst told the NBC ``Today'' show Tuesday.

One student said he had a smile on his face as he fired away with a .22-caliber pistol.

``It was total chaos. People were trying to take cover,'' said student John Schardt, 17, who was in a nearby classroom when the shooting started about 9:20 a.m. in a boys' restroom.

Police Lt. Jerry Lewis said the teen-ager shot two people in the restroom, then walked into a quad and fired shots randomly. He stopped to reload his weapon as many as four times, getting off 30 or more shots, Lewis said.

``The bell had rung to go to class and we were all walking to go to class and all of a sudden you hear the sound of like a cap gun,'' said student Jennifer Wall.

``Pop, pop, pop and everyone started ducking,'' recalled fellow student Nika Ocen-Odoge.

Andrew Kaforey, a 17-year-old senior, said he ran into the bathroom with a security guard after hearing what sounded like a firecracker or a gunshot. ``He pointed the gun right at me but he didn't shoot,'' Kaforey said.

As he and the guard ran out, Williams shot the guard in the back, Kaforey said.

Williams finally surrendered in the bathroom, dropped his gun and said he acted alone, telling officers: ``It's just me,'' according to authorities.

Students Bryan Zuckor, 14, and Randy Gordon, 17, were killed. Zuckor was killed in the bathroom; Gordon was wounded on the quad and died at a hospital.

Eleven other students, a 29-year-old student teacher and a 22-year-old campus security guard were wounded. Another student suffered minor injuries when he crashed his car fleeing the campus.

The injured were taken to hospitals. Some were released after being treated, while others were listed in good condition.

``We have established no real motive,'' Lewis said about the shooting. ``He did not have any particular targets in mind.''

But fellow students and an adult acquaintance said they had heard the boy's threats over the weekend.

``He's a good friend. If he was joking, I wouldn't want to get him in trouble,'' O'Grady said.

Recently, two skateboards had been stolen from the boy, O'Grady said, adding, ``He always gets picked on. He's scrawny, he's little.'' Another friend, Josh Stevens, told the ``Today'' show that one of the people who took a skateboard was among those shot Monday. He didn't elaborate.

Friends also mentioned a recent scrape involving alcohol and a girl, a death of a friend in Maryland, where Williams used to live, and a beating at a local skateboarding park.

``He was picked on all the time,'' student Jessica Moore said. ``He was picked on because he was one of the scrawniest guys. People called him freak, dork, nerd, stuff like that.''

Chris Reynolds, 29, whose girlfriend's son is a friend of Williams, said the boy stayed at his house Saturday night and talked about going on a shooting spree.

``I even mentioned Columbine to him. I said I don't want a Columbine here. But he said, `No, nothing will happen, I'm just joking,''' Reynolds said.

``I should've stepped up even if it wasn't true and stuff to take that precaution,'' said Reynolds. ``That's going to be haunting me for a long time.''

Williams will be charged as an adult with murder, assault with a deadly weapon and gun possession, and could face multiple life terms, Pfingst said. He was to be arraigned Wednesday.

Sheriff's and FBI officials Monday night searched the apartment where the teen lived with his father. They removed seven rifles, a computer, a plastic crate filled with papers and files, and about a half dozen bags filled with evidence.

The boy's mother, who is divorced from the father, lives in South Carolina. The New York Times said Linda Wells sobbed, ``Oh, God. Why?'' when told that her son was the suspected shooter.

After the shooting, students were escorted to a nearby shopping center, where they filled a parking lot and milled anxiously while parents arrived and paramedics took away the wounded.

About 1,000 people gathered Monday night at Sonrise Community Church in Santee for a memorial service.

``We want to just know why,'' Mayor Randy Voepel said. ``I must tell you that it will be years and years of healing that we will have to face.''

Students, many wearing purple and gold ribbons representing their school's colors, buried their heads on each other's shoulders and cried.

``Until today, I didn't understand the reality,'' said Tina Ayo, placing an arm around her sobbing 15-year-old daughter, Jenna.

Grief counselors were called in to counsel the 1,900 students at the school, where bouquets, cards and other tributes quickly piled up.

The attack was the nation's deadliest school shooting since the April 1999 blood bath at Columbine High near Littleton, Colo., where two teen-agers killed 12 fellow students and a teacher before committing suicide.