Andy John Ulsaker's mother had premonitions all day that her son might get in trouble that night at a concert by the Rolling Stones.

Mothers have had premonitions like that ever since the Stones began performing in England in the early '60s. They were a hard-edged band that always flaunted an image of sex and violence -- an image that June Ulsaker was well aware of in her native England. "Violence goes with this group," she recalls thinking Tuesday, remembering the times she had seen the band on the telly back home.

So the premonitions persisted . . .

And at about 7:30 Tuesday night, they came true:

As he stood in a cornfield east of the Capital Centre, a bullet struck Andy John Ulsaker in his side. A few paces away, his friend and roommate Richard L. Wright lay on the plowed earth, blood trickling from his mouth.

One hour later Wright was dead.

Late last night, Prince George's County Police arrested John S. Mauthe, 21, of Pikesville, and charged See FAN, B19, Col. 1 FAN, From B1 him with the murder of 21-year-old Wright. At midnight, Mauthe was still being questioned, and police would not proffer a motive for the crime.

Tuesday night, June Ulsaker was standing beside her 21-year-old son in the emergency room of Prince George's County General Hospital. It was the first anniversary of the assassination of John Lennon, and several hours after she had looked at the clock on her microwave oven and tried to telephone her son, to beg him not to try to see the Stones.

This is what she says he has told her about the shooting, although police have not come up with an independent confirmation:

The two young men from Beltsville had tried to buy tickets for the concert from scalpers around the Landover sports arena. They had been offered tickets for $45. They thought they'd wait until about 10 o'clock, when the Stones were expected to go on, to see if the prices would come down. They drank a couple of beers. They walked into the cornfield to urinate.

Andy John Ulsaker had told his mother about that cold, wind-whipped cornfield before. "He said if he had a ticket he was going to stick it in his boot," she said, "and he was going to stay away from that cornfield, because he said that that's where kids got rolled for tickets."

But apparently he didn't remember his own warning.

Perhaps the call of nature was too strong.

The 6 foot 1 inch Ulsaker had his back to the shorter Wright. They were both out there together. Ulsaker noticed a man and a woman come up to Wright and heard the beginning of a dispute:

Man: "You got any tickets?"

Wright: "No, you got any tickets?"

Man: "Bull----, you've got the tickets!"

Wright: "Bull----. We don't!"

At this point Ulsaker turned around to see what the commotion was about, and he was hit in the side by a bullet. At first he thought the noise might be firecrackers going off, but the impact of the bullet fired from a handgun knocked him to the ground. He got up to check on his friend and found him lying on the ground with blood coming out of his mouth.

"Bobby, are you all right," he asked his roommate.

"I think so."

Ulsaker ran for the police. And in moments the two friends were rushed together to the hospital, June Ulsaker said in concluding her version of her son's memories.

The two young men had been together many times before. They met at High Point High School, where Ulsaker was graduated in 1978. He had grown up around the world, lived in Africa, the Caribbean and Asia, because his father was an agricultural economist with the State Department. The family moved to the Washington area in 1974 to fulfill a promise that Andy graduate from an American high school.

The young men shared an interest in rock 'n' roll. And they worked together for a roofing firm in Silver Spring. "He couldn't hack a nine-to-five job," June Ulsaker said of her son. "He loved to sail and to ski." Two months ago, with the help of Ulsaker's parents, the young men found an apartment to rent in a condominium at 11346 Cherry Hill Rd. Ulsaker would often eat meals with his parents, and then return to the apartment.

Efforts to reach the family of Richard Wright were unavailing. Andy John Ulsaker spent last evening in stable condition, a hospital spokeswoman said.

Prince George's Police Sgt. Robert Law said, "At first the boy said it was two males who approached them. Then he said a male and a female, with the female off at a distance. It could have been a male with long hair. They're Ulsaker talking about tickets. We're not aware of any previous incident with anyone being shot over tickets, but since they've said that we're focusing on the ticket issue." According to Sgt. Law, the police are also looking into whether drugs were involved.

"If it was drugs, he would have told me," June Ulsaker said. "He was very up-front with us.

"I hope they catch the person. I would like to look in his eyes and see what kind of person could shoot my son over a ticket."