THE HEADLINES grabbed attention, screaming the tragic tale of a missing woman found dead in a car parked near 30th Street Station and littered with parking tickets.

Even London's Daily Mail published the story of Nadia Malik, 22, and the mysterious circumstances surrounding the discovery of her body, a year ago today, in a black Nissan Altima.

But despite the initial media blitz and the dozens of stories that followed, a year later the case has not been solved and a crucial question remains:

How did Nadia Malik die?

Officials say they haven't been able to figure that out.

Meanwhile, new details have arisen about Malik's past, including the death of her infant daughter, also under a cloud of suspicion.

And law-enforcement sources, stretching across several jurisdictions including the city and Malik's native Delaware County, tell the Daily News that not enough evidence has been found to bring charges against the man who has been under a microscope since the day she disappeared.

For months, the city medical examiner told reporters that the cause of Malik's death was under investigation, and that the information was pending because of detailed toxicology tests.

When investigators found her body slumped in the Nissan's passenger seat, "articles of clothing and a backpack . . . had been placed over the body," said Marple Township Police, with whom the Malik family had filed a missing-person report.

They found no sign of physical trauma.

In October, police investigators handling the case said the testing was inconclusive and her cause and manner of death "undetermined."

Last week, Jim Garrow, a spokesman for the city Medical Examiner's Office, told the Daily News that "after extensive research," the office couldn't find "any toxicological or anatomical cause" for Malik's death.

In other words, authorities were stumped. Garrow said he couldn't recall the last time his office had made such a ruling.

Not a first for family

It was not the first time the Malik family had suffered a loss shrouded in mystery.

On Feb. 28, 2012, Alina Singh, Nadia's 3-month-old daughter with longtime boyfriend Bhupinder Singh, was found unresponsive inside a car parked near a Chinese restaurant in Springfield, Delaware County, and was pronounced dead later that day, according to a spokesman for the county Medical Examiner's Office.

The infant's mother, sitting in the car beside her when medics arrived, would be found dead in another car almost two years later.

Last July, the Delaware County Medical Examiner ruled that the cause of Alina's death was cachexia - a type of muscle atrophy colloquially called "wasting syndrome," which usually accompanies an underlying condition.

Her manner of death was listed as undetermined, and remains so today.

Despite these ambiguities - or perhaps because of them - the investigation into Malik's death is still active. It's being handled by Philadelphia Police and the Philadelphia District Attorney's Office.

Cameron Kline, a spokesman for the D.A.'s office, declined to comment, citing the open case.

A police source, who spoke on the condition of anonymity because the probe is ongoing, said that without a definitive ruling from the medical examiner on whether Malik was killed, charges can't be filed with the D.A.'s office.

The source said there's "not enough probable cause" to arrest Bhupinder Singh, with whom authorities say Malik was last seen alive on Feb. 9, 2014.

When the body was found days later, Singh was sitting in a jail cell in Ohio, waiting to be hauled back to Delaware County. He had been arrested for skipping town while on probation for a 2010 DUI conviction, police said.

When he was arrested Feb. 12 at his parents' apartment in Solon, a suburb of Cleveland, he was holding Malik's driver's license and cellphone, according to documents from the Solon Police Department.

He later admitted that he had used the phone to send antagonizing text messages to Malik's family.

Copies of those texts, obtained by the Daily News, show that Singh said he would let them talk with her in exchange for $100.

When they balked, Singh wrote: "Okay think whatever bye I promise u this now u wont hear her ill f---in make sure bye u lost the chance."

"Look for us in the whole United States, I guarantee my life u wont find us," he threatened in another message.

Hoping for truth

Singh, 26, told police that he fled to Ohio on a Greyhound bus from New York after getting into an argument with Malik "concerning their relationship," according to the documents from Solon.

He told officers that he didn't know where Malik was, and hadn't learned that she had been found dead until after his arrest, according to a report filed in Delaware County after Singh's extradition.

Singh was found guilty of violating his probation in April and was jailed for a month, court records show.

He's now out on parole and living in Upper Darby. Mark Phillip Much, Singh's lawyer, did not respond to calls from the Daily News seeking comment.

A law-enforcement source with inside knowledge of the case told the Daily News that Singh is still a "potential suspect" in Malik's death, but that no charges have been filed.

"Only one person knows what happened," the source said. "And he ain't talkin'. "

The Malik family also declined to comment for this article.

One family member said that Malik's siblings are grateful for the support offered to them and are hoping that one day the truth will be revealed.

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