Singh was sentenced last month to four to 23 months in jail for violating his probation from a 2010 DUI case. He had fled to his parents' house in Solon, Ohio, the day before Nadia was reported missing, police said.
One condition of that sentencing was that Singh could only be released on a parole plan that included monitored house arrest, according to court records.
Marple Township Det. Barry Williams said the investigation into Nadia's slaying is on hold, pending results from toxicology tests from the city Medical Examiner's Office.
"We're still waiting for the final results to determine what to do with [Singh]," Williams said.
But members of the Malik family say they don't need any more evidence: To them, it's clear who took Nadia's life.
Khaled Malik provided the Daily News with text messages allegedly sent by Singh through Nadia's phone that taunt the family, saying they'll never see her again - texts that Singh later admitted to police he sent.
"If you get into a fight with your girlfriend, you don't run to a different state, you don't run out the back door when cops come to you," said Mona Malik, Nadia's sister. "Those are things you just don't do, and he has no answer for any of them."
While the probe into her sister's death is in limbo, Mona Malik has started an online campaign calling for what she believes are necessary reforms to how the city investigates abandoned cars.
In a petition on Change.org, she implores Mayor Nutter to institute a policy that would require cars with multiple parking tickets to be scanned for possible involvement in criminal investigations.
"If she had been found sooner, this mystery could have been solved," Malik said. "The circumstances are all working for [Singh] now."
Marty O'Rourke, a spokesman for the Philadelphia Parking Authority, said that under the current policy, cars with three ignored tickets (those left untouched on the windshield) become the subject of an abandoned-vehicle report, which is then turned over to police.
Those reports are received by the police's neighborhood-services division, which investigates each case and seeks to find the vehicle's owner, according to police spokesman Lt. John Stanford.
Whatever the outcome of her campaign and ultimately the investigation into Nadia's death, Mona Malik is confident that justice will come to Singh.
"I believe in God; he's the ultimate judge," she said. "In God's time, [Singh] will answer to what he did."
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