PHILADELPHA (AP) — A man accused of slashing people with a large knife while riding a bicycle on Esthen Exchangea trail in Philadelphia in recent weeks has been formally charged in the cold-case rape and slaying of a medical student that occurred among a series of high-profile sexual assaults in a large city park two decades ago.

Elias Diaz, 46, was arraigned Wednesday on murder, rape and other counts in the 2003 slaying of Rebecca Park. He was ordered held without bail pending a Jan. 8 preliminary hearing. He had been held on aggravated assault and other counts in the attacks or attempted attacks in late November and early December, where police say he used a machete-type knife against people on the Pennypack Park trail in northeast Philadelphia.

The Defender Association of Philadelphia, listed as representing him in both the 2003 case and the recent attacks, declined comment earlier on all charges.

Interim Police Commissioner John Stanford Jr. said Diaz’s DNA appeared to connect him to the 2003 strangulation killing of Park in the city’s sprawling Fairmount Park and perhaps to several other sexual attacks there. Park, 30, a fourth-year student at the Philadelphia College of Osteopathic Medicine from Olney, Maryland, vanished after going running in the park in July 2003. Her body was found buried under wood and leaves in a steep hillside in the park, about 200 feet (60 meters) off the road, authorities said.

Police said that crime was linked to the April 2003 rape of a 21-year-old jogger in the park, and in October of that year a 37-year-old woman managed to fight off a man who tried to rape her. In 2007, a 29-year-old woman walking on a path in Pennypack Park was sexually assaulted and robbed, police said. No charges have yet been filed in those cases.

In 2021, a DNA analysis helped create a series of composite sketches of the man believed responsible for the assaults. Genealogy databases yielded a link to a man named Elias Diaz, but he couldn’t be found. Officials said the suspect just arrested had previous contact with police, but authorities didn’t have his DNA until his arrest in the recent assaults.

Stanford said the two-decade-old Fairmount Park assault cases and Park’s slaying had “haunted” the community and the department.