Autopsies on the bodies of four women found in a drainage ditch behind a string of seedy motels just outside Atlantic City determined that two were murdered — strangled by a rope or cord — but the other two bodies were too badly decomposed for authorities to say for sure what caused their deaths.

The mystery deepened Wednesday when investigators revealed that shoes and socks were removed from all of the victims, each body was left in the same ditch within a few hundred feet of each other; and, each woman's head was facing east, toward Atlantic City's casinos.

Those revelations fueled speculation — and fear — on the streets that police were dealing with a ritual or serial killer, possibly targeting prostitutes in the area.

Atlantic County Prosecutor Jeffrey Blitz said there are indications the women may have been placed in the ditch at different times, based on varying degrees of decomposition of the bodies.

"The fact that they're all being dumped at this common dump site and they're all there without their shoes and socks on, then we've got to presume at this point, that we are dealing with one killer," former FBI profiler Jack DiMarco told FOX News. "But you also have to presume at this point … that they were either prostitutes, they were either drug users or they were just people that were in the wrong spot at the wrong time."

If the victims were prostitutes or involved in local drug rings, DiMarco said it would pose more problems for law enforcement in tracking down the killer. Most people who may have knew the victims likely are transients or won't be as willing to cooperate with police, he added.

The fact that one body was placed in the water — yet not deep enough to hide it — may suggest the killer was trying to destroy evidence on the body, DiMarco added.

"The perpetrator is probably thinking he's doing away with evidence," he said, adding that the shoes and socks may have been taken by the killer as "souvenirs."

The first two victims' autopsies indicated they had died a few days to as long as a week before they were discovered Monday. An autopsy on the third victim concluded that she may have been in the water for at least two weeks.

The only woman authorities have been able to identify thus far, 35-year-old Kim Raffo, died from strangulation.

Raffo was described as "the mom of the year" by her sister, before a streak of marital discord and drug abuse four years ago.

Maria Santos said Raffo was raised in Brooklyn and moved to Florida at 18. She later married her longtime boyfriend and, by the time she was 30, was a longtime housewife, a PTA mom and a dedicated aunt.

But Raffo became bored with her life and briefly tried cooking school before having an affair with a man who gave her crack cocaine.

Raffo's husband then left her, taking their two children — now 14 and 12 — to New Jersey, where the children are now in foster care.

Raffo eventually was caught with drugs and arrested, then later returned to New Jersey. And despite efforts to locate her, Santos never heard from her sister again.

Raffo's current boyfriend, Charles Coles, said Raffo had been working as a prostitute in Atlantic City since September.

"It hurt her and broke her down," he said. "She was trying to get her life together to get her kids back."

Bill Southrey, president of the Atlantic City Rescue Mission, said Raffo stayed at the mission for one day last year, and two days in January.

It was not enough time for the shelter to get to know much about her. But Southrey said files show she had struggled with drug addiction and came to the mission because she had lost her place to stay with a friend. She talked of trying to get a job and moving to Florida. Records show she had lived in Broward and Miami-Dade counties in that state.

Southrey said the people he helps are upset, even if they did not know the one victim who has been identified.

"It's very shocking when there's a horrific crime committed in their backyard," he said.

Anyone with any information on the killings is encouraged to call a tipline at 1-800-658-8477 (TIPS).

The Associated Press contributed to this report.