Man, 18, Sought in 2 Slayings : Crime: He is suspected in a shooting rampage that left his ex-girlfriend critically wounded and her mother and sister dead in West Covina.

Police were searching Wednesday for a jealous teen-ager suspected of a shooting rampage that left his former girlfriend critically wounded and her mother and sister dead in their home in an affluent West Covina neighborhood.

Matthew Lee Walker, who was scheduled to begin a jail sentence Friday for assaulting the girlfriend in January, is believed to have stolen her family’s 1985 black Mercedes-Benz and headed for Canada.

Walker, 18, an unemployed construction worker, was described as having blue eyes, a light brown crew cut and numerous tattoos, including a face of the “Grim Reaper” on his left arm and, on his left leg, the phrase, “I hate the world.”

The former West Covina High School student on Tuesday allegedly entered the three-bedroom home of Erwin and Evelina Teschner, who had lived on a quiet cul-de-sac in the 1200 block of Shasta Drive since 1974.

Walker’s 17-year-old ex-girlfriend, West Covina High student Tracy Teschner, was shot in the head with a small-caliber handgun and remained hospitalized in critical condition Wednesday night, police said.

Her sister Tanya, 18, who was to be a finalist for queen of her Bishop Amat High School senior prom tonight at the Disneyland Hotel, was found dead, shot in the head.

Also killed was the girls’ 53-year-old mother, who neighbors said worked as a nurse or medical technician in a nearby hospital.

Their bodies were discovered shortly before 5 p.m. Tuesday by Erwin Teschner, who owns a Pomona plastics factory that has about 12 employees. He was reportedly with relatives on Wednesday.

“He was just hysterical,” said William Hoffman, a neighbor who called police after Teschner came to his door for help. “He couldn’t believe what had happened to his family.”

According to court records, Walker and Tracy broke up last July, after dating for about four months. But Walker continued to harass her at home and at school, the records show.

Tracy had been reluctant to call police because Walker had threatened to harm her if she did, the documents say.

Then, on Jan. 28, Walker jumped from the bushes outside Tracy’s home as she accompanied a male friend to his car. The records show he punched her in the neck and pushed her against a fence.

“I saw you kissing him,” Tracy reported him as saying, according to a police report. “If you do that again I’ll kill you.”

On April 16, court records show, Walker pleaded no contest to battery and was sentenced to four days in county jail, placed on two years’ probation and ordered to attend counseling sessions.

“He’s a young man known to a lot of students . . . as violence-prone,” said West Covina Police Cmdr. John Distelrath. “He loses his temper easily.”

Tanya Teschner had made similar comments about Walker to her boss at Clothestime in a West Covina mini-mall, where she had worked part time after school as a sales clerk for the last 10 months.

“The way she explained it, it was like a fatal attraction-type thing,” said store manager Lisa Rubi.

Rubi said Tanya told her that Walker sneaked into the Teschner home one night after the breakup, crawled into bed with Tracy and hugged her while ordering her not to say a word.

“Tanya was was really scared by him,” Rubi said. “This is so unfair.”

That was the sentiment of classmates at the two girls’ schools, where classes were interrupted Wednesday for grief counseling sessions.

Classmates of both Tanya and Tracy called the girls popular and high-spirited, although Tanya was described as being quieter and more studious while Tracy was slightly more outgoing and free-spirited.

“Tanya was like the happiest girl on Earth,” said Father James Anguiano, principal of Bishop Amat, a Catholic school in La Puente. “Always smiling and laughing. Just full of life.”

Tanya had attended Bishop Amat for four years and was scheduled to graduate June 7. She was the senior class secretary and planned to study business next fall at Cal State Fullerton.

Tracy had attended Bishop Amat for her freshman and part of her sophomore year, but then transferred to West Covina High, where she worked with children as part of the school’s child development program.

“She was nice and sweet,” said classmate Chad Wilson, 18. “She’d always bring a smile to you.”

Walker, whose last address was in Apple Valley, is believed to be driving the family’s Mercedes 300SD, a four-door with California license plates of 2UTK648, police said.

Border Patrol and custom agents have been notified that he might be trying to flee the country, according to Distelrath.

At the Apple Valley home, a young man who identified himself as Walker’s brother declined to speculate on where Walker might be or whether he had been involved in the shooting.

“That’s nothing to tell you about,” he said when contacted by phone.