Philadelphia police are investigating four weekend killings, including that of a partially clad woman who was found stabbed and bludgeoned on a park path in North Philadelphia.

The other victims were men who had been shot.

As of Monday morning, no arrests had been made in any of the weekend homicides and investigators were continuing to search for suspects. The motives remained unknown in all four slayings, and no information about potential suspects was available in any of the cases.

The slain woman, identified Monday as 33-year-old Debra Gulliver, was found shortly after 3 a.m. Saturday, on a path to Reyburn Park behind Dobbins Technical High School on the 2100 block of West Lehigh Avenue in North Philadelphia. Her body was discovered by someone who had just been robbed by two men inside the park, police said.

Gulliver, of North Philadelphia, was partially clothed and had been stabbed several times in her abdomen and suffered blunt-force trauma to her head, police said.

She was pronounced dead at the scene at 3:21 a.m. It wasn’t known how long she had been at the park.

“Her condition shows an awful experience that she must have gone through. She was stabbed repeatedly,” Capt. Drew Techner told reporters at the scene over the weekend. “Somebody didn’t just stop once or twice or three times. They just kept stabbing this woman all throughout her body.”

Also over the weekend, three men were killed in separate shootings in the city.

The most recent of those happened at about 11:20 p.m. Sunday, when 25-year-old Nino Rivera, of Hunting Park, was shot in his back and head on the 500 block of East Allegheny Avenue in Kensington.

Rivera, who was found on the street, was pronounced dead at the scene at 11:23 p.m.

Less than two hours earlier, another man was shot dead on the 5600 block of Arch Street in West Philadelphia. Officers were called to that location for a report of a shooting about 9:30 p.m. Sunday.

Brian Johnson Jr., of Parkside, was taken in a private vehicle to Penn Presbyterian Medical Center, where he was pronounced dead at 10:02 p.m. The 31-year-old had been shot in his back and arm.

The Sunday deadly shootings followed the killing early Saturday of a 49-year-old man in the Harrowgate section of Kensington.

The man, whose name has not been released because his family has not been notified, was found suffering from a gunshot wound to his stomach in a park on the 1800 block of East Tioga Street about 1:20 a.m. Saturday.

He was taken to Temple University Hospital, where he died at 2:48 a.m.

[Update: An earlier version of this post gave the wrong age for Debra Gulliver. She is 33.]