Rebecca Park cold case: Pennypack Park slashing suspect believed to be Fairmount Park rapist

Police say Elias Diaz is the prime suspect in the 2003 murder of Rebecca Park. He may also be tied to other assaults.

Pennypack Park slashing suspect believed to be Fairmount Park rapist
The man believed to be the infamous Fairmount Park rapist has been taken into custody, Philadelphia police sources said Tuesday.

PHILADELPHIA (WPVI) -- A machete-wielding man arrested for a series of knife attacks last month is now the prime suspect in connection with a 20-year-old cold-case killing in Fairmount Park.

Elias Diaz, 46, was arrested on December 17, 2023, following two slashings on the Pennypack Park trail in Northeast Philadelphia.

Police say DNA collected from Diaz this week has ties to the infamous Fairmount Park rape cases, including the death of Rebecca Park, who was attacked and killed while she jogged alone in the park on July 13, 2003.

Authorities believe he'll be tied to other assaults after further DNA testing is returned.

"Everything we have at this point leads us to believe that Mr. Diaz is also involved, or a person of interest, regarding the murder of Rebecca Park, which occurred in July of 2003, as well as possibly two or three other sexual assaults that occurred in Fairmont Park over a period of time," said Interim Police Commissioner John Stanford.

FULL NEWS CONFERENCE: Police name person of interest in Fairmount Park rape cold case

Authorities say Diaz may face charges in connection with Park's death as early as Tuesday.

"I fully anticipate on charging Elias Diaz with murder and related offenses with regard to the homicide of Rebecca Park that dates back to 2003. I fully anticipate that we will have the results of the DNA before (Tuesday) is out, and I will call in those charges for murder and many other offenses with regard to the case of Rebecca Park," said Joanne Pescatore, the chief of homicide for the Philadelphia District Attorney's Office.

These are the type of cases that haunt you until you're able to bring some closure to it
Interim Police Commissioner John Stanford

Slashings in Pennypack Park

The first slashing attack happened around 8:15 a.m. on Nov. 22, 2023, in the area of 2800 Holme Avenue.

Police say the victim was running on the trail and was approaching a bicyclist from behind. As the runner announced his approach, the bicyclist, who has since been identified as Diaz, became enraged.

The victim said that the bicyclist pulled out a large knife, possibly a machete, and slashed him multiple times in the arms and hands.

SEE ALSO: DNA tool may help in Fairmount Park rapist cold case

Then, around 9 a.m. on Nov. 24, 2023, a person walking along the trail in the area of 2800 Winchester Avenue was attacked by a bicyclist with a large knife.

The victim was cut on his right arm and hands.

Diaz faces charges of Attempted Murder, Aggravated Assault, and related offenses in connection with the slashing attacks.

Suspect sought after 2 people slashed on Pennypack Trail in Northeast Philadelphia

Cold case rapes

Rebecca Park, 30, a fourth-year student at the Philadelphia College of Osteopathic Medicine from Olney, Maryland, vanished after going running in Fairmount Park in July 13, 2003. Her body was found buried under wood and leaves in a steep hillside in the park, about 200 feet off the road, authorities said.

In 2003, police were able to use DNA from Park's murder and link it to two other attacks that year in Fairmount Park: a rape of a 21-year-old jogger on April 30, 2003, at Kelly Drive and Fountain Green Road, and an attempted rape of a 37-year-old woman on October 25, 2003, at West River Drive near the Falls Bridge.

Four years later on August 11, 2007, the serial rapist struck again -- this time in Pennypack Park. Police say a woman, about 25 years old, was raped near Frankford and Solly avenues while walking on the trail. It's not far from the 2023 slahsing attacks, police said.

How DNA helped the case

Since the investigation began, authorities scoured the crime scenes to collect DNA evidence. It was submitted into the DNA database, otherwise known as CODIS. But it was ultimately a genealogy tracing that led to one suspect.

During a 2021 press conference, police released new images of what the suspect may look like using DNA phenotypic analyses, which uses DNA to predict the physical characteristics of the subject.

Philadelphia police released new images on Thursday showing what the infamous Fairmount Park rapist could look like today as the search for him continues.

Philadelphia Police Lab Manager Ryan Gallagher says the same DNA was also entered into public genealogy databases, which helped build a familial profile for the serial rapist. In April of 2023, that investigative work led them to the name of Elias Diaz, but police weren't certain if he was still alive.

"We had no idea if he was even still living. There was information given to us when we started to search for him, and they started searching for him, that he was in the area Kensington. Somebody said he overdosed. No one had seen him for a time. So we had no idea where to find him or if he was living at a residence or was unsheltered," said Interim First Deputy Commissioner Frank Vanore.

SEE ALSO: Philadelphia police release new images of what Fairmount Park rapist could look like today

Diaz was in custody for two crimes in 2007 and 2015, but it was the November machete attacks in Pennypack Park that linked his DNA to the Fairmount Park rapist case.

Chopper 6 was overhead on Dec. 19, 2023, as investigators spent hours searching a makeshift tent and campsite where sources tell Action News Elias Diaz lived.

The latest search

After news broke about Diaz's possible connection to the cold case Tuesday, authorities descended onto an area at Pennypark Park behind Lincoln High School.

Chopper 6 was there as investigators spent hours searching a makeshift tent and campsite where police tell Action News Elias Diaz lived.

Authorities say Diaz used the area as shelter, but it remains unclear where he's been hiding through the years.

Diaz has not faced any charges in the Fairmount Park rapist case.

Stanford said the Fairmount Park assault cases and Park's slaying had "haunted" the community and the department, pointing to the presence of retired Capt. John Darby, who had just assumed command of the special victims unit when the assaults began.

"This was important enough for him today to come back," he said. "These are the type of cases that haunt you until you're able to bring some closure to it."

Darby echoed his words, saying "Investigators will tell you, they go home, the last thing they think about before they go to bed at night, the first thing they think about when they wake up in the morning, is cases like these."

Elias Diaz was in custody for two crimes in 2007 and 2015, but it was the November machete attacks in Pennypack Park that linked his DNA to the Fairmount Park rapist case.

The Associated Press contributed to this report.