11 Investigates: Pennsylvania’s 1st serial killer?

BEAVER COUNTY, Pa. — Police believe he may have been Pennsylvania’s first serial killer.

He was convicted of one murder, the prime suspect in two others and police believe there could be more.

Channel 11 Chief Investigator Rick Earle took a look at the chilling disappearance of a 15-year-old girl in Beaver County that launched the investigation into Pennsylvania’s first serial killer.

“In 1958, the nice little town of Baden, and no crime in Baden. It’s like Mayberry,” said Beaver County Chief Detective Andy Gall.

Beaver County Chief Detective Andy Gall was 4 years old when 15-year-old Becky Triska vanished.

It’s a case his mother would often reference as he was growing up.

“My mother would say, ‘When you get to your buddy’s house you call me.’ I said, ‘Mom, nobody else has to do that, what are you talking about?’ ‘Not going to happen to you what happened to Becky Triska.’ So, I lived with that forever,” said Gall.

Today, more than six decades later, it’s one of Detective Gall’s oldest unsolved cases in Beaver County.

On a September night in 1958, Triska, a typical teenager, left her home in Baden to go to a dance in Ambridge.

She never made it home.

“Never came home. She had people at the dance who saw her. She was going to ride the bus back. There was a lot of bus traffic at that time,” said Gall.

Gall said some friends saw her after the dance outside a popular local restaurant.

They told police that an older man in a car was trying to pick her up.

“One of the other high school kids who didn’t know this man told him, ‘You’re too old for her, get out of here,’” said Gall.

Investigators at the time linked that car to Frank Senk.

While questioning Senk, he admitted his girlfriend was underage.

Police put him in jail on a morals charge, as they attempted to prove he killed Triska.

“They could never get the case to a point where they could file charges on Senk,” said Gall.

Senk was eventually released from jail.

Three years after Triska’s disappearance, Senk was convicted of sexually assaulting and killing a 13-year-old girl in Centralia, Pennsylvania.

He would also become the prime suspect in the murder of a 15-year-old girl found in a dump in Hopewell township in 1949, nearly a decade before Triska’s disappearance.

“There’s a good possibility he would be one of the first persons that we could call a serial killer in Pennsylvania,” said Gall.

Senk also served time for rape in Florida, and Gall believes he was involved in other crimes as well, although he was never charged with them.

“We found a couple of other sexual assaults that are attributed to him all across the state of Pennsylvania,” said Gall.

While Senk confessed to the murder in Centralia, he denied any involvement in Triska’s case. He said he was at a football game with his girlfriend. She corroborated his story.

But as Gall was going through the evidence one day, he found red hairs investigators had recovered from Senk’s car in 1958 that they believed belonged to Triska.

Senk said they were from his niece.

Gall sent those samples to the FBI lab.

“They came back and says all the DNA was basically ruined, basically by people looking at it like this. They could not be tested,” said Gall.

Senk was sentenced to death for the murder in Centralia, but his sentence was later commuted to life in prison.

He died of cancer while in prison.

Today, 65 years later, Gall has no doubt that Senk was involved in Triska’s disappearance and death.

Earle: You’re confident he was your guy?

Gall: I’m confident. I can tell you with today’s technology that those red hairs would have been what sunk him.

Earle also learned that authorities had a chance to stop Senk when he was in jail during the Triska investigation, but the Pennsylvania Welfare Department ruled that Senk was not a habitual offender and did not need psychiatric treatment. He was released from jail and would later be arrested and charged with the murder in Centralia.

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