PHILADELPHIA (CBS) — Philadelphia police on Thursday released three aged-progressed digital composites of a suspect in their investigation into the “Fairmount Park Rapist,” a serial sexual assault and homicide suspect who started his attacks in 2003.

Police say investigators used new technology to produce the sketches based on DNA evidence they say show what the suspect may have looked like during the attack at age 25 as well as at age 40 and what he could look like at age 60. Detectives say they hope it’s a fresh look that can help in identifying who he is.

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The “Fairmount Park Rapist” is connected to at least four sexual assaults, one of which police say was a homicide, from 2003 to 2007.

The incidents happened within a one-mile radius and DNA evidence linked the incidents to one suspect, investigators said.

“He was armed with a knife that he held in his left hand each time,” Cpt. Mark Burgmann with Philadelphia’s Special Victims Unit said Thursday.

The alleged sexual assaults began on April 30, 2003, when police say a 21-year-old woman was raped at knifepoint by a man while she was jogging on Kelly and Fountain Green Drives.

Then, on July 13, 2003, 30-year-old Rebecca Park was jogging in West Fairmount Park when, according to police, she was raped and strangled to death. Police said her body was discovered four days later.

Police said the suspect struck again on Oct. 25, 2003, attacking a 37-year-old woman, who was jogging on West River Drive, at knifepoint. According to the police, the victim escaped.

Investigators believe the same suspect was responsible for a rape near Frankford and Solly Avenues on Aug. 11, 2007, four years after the first three attacks.

Police said the victims all gave similar accounts of what the suspect looked like.

(Credit: Philadelphia Police Department)

The suspect is believed to be a Hispanic man with a Latino accent, around 5-foot-8 with black hair and a thin mustache or jaw-line beard and bushy eyebrows at the time of the attacks. He was described to police as having a widow’s peak hairline, and in two of the incidents, he was reportedly wearing an earring in his left ear.

Police said he was seen fleeing the scene of the crimes on a purple metallic 10-speed bike.

“Although these cases are decades old, the scars left behind from this offender’s actions still impact his victims and their families today,” Philadelphia Police Commissioner Danielle Outlaw said in a statement. “In addition, many of the investigators who worked these cases are still haunted by the callousness and brutality of these attacks. The Philadelphia Police Department has never forgotten about this offender’s actions and the effects of his actions on those around him.”

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While the serial rapist was never caught, many runners and joggers Eyewitness News talked to Thursday believed he was behind bars.

“It is surprising that he hasn’t been caught,” one runner said.

“The safety of, especially the runners or anyone who’s walking around here, is still import, even after all these years,” another runner said, “because, we don’t know if someone’s still there.”

But as the case stalled, technology kept moving forward.

“The technology itself is called [PhotoDNA],” Ryan Gallagher, the forensic lab manager, said.

The technology used to create the new sketches took DNA from possible relatives found on public ancestry databases along with the suspect’s DNA.

This is the first case the technology has been used by the Philadelphia Police Department.

“It uses data from tens of thousands of genes along your DNA that predict physical characteristics such as hair color, eye color, skin color, and freckling,” Gallagher said, “and combining that with information about ancestry and facial model they’re able to use all that information to come up with a composite sketch.”

The new composite sketches of the suspect like the sketch previously released by police but with more defined features.

“One of the victims did say that facial features look similar,” Det. Roy Kahlan said.

At this time, investigators said they do not have any leads on the suspect.

Police are not sure if the suspect remains in the area or if he has since moved. Police say another theory is that the suspect may have died.

Anyone with any information is being asked to contact investigators at 215-686-8477.

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CBS3’s Matt Petrillo contributed to this report.