Richard Petrone Jr. and Danielle Imbo vanished on Feb. 19, 2005.
On the 10th anniversary of their disappearance, investigators announced their continued commitment to solving the case. The case is now part of the FBI's Cold Case Initiative, meaning more time and resources will be dedicated to the investigation.
The pair, long-time family friends who had once dated, were last seen leaving a South Street bar together shortly before midnight, Richard, 35, telling friends he’d drop Danielle, 34, off in South Jersey before returning to his South Philly home.
They were never seen or heard from again.
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Richard’s truck, a black 2001 Dodge Dakota, has never been spotted. Their cell phones and financial records went dead the day they disappeared.
Authorities have pursued hundreds of leads and listened to thousands of tip calls. Searches were conducted on the ground and by air, and waterways were combed. The nature of the crime has led investigators to conclude it was a planned attack acted out by more than one person.
"We feel this was an orchestrated act. A 3,000 pound truck and two people do not simply go missing," said Christian Zajac, an agent with the FBI's criminal branch division.
"It is unlikely based on law enforcement experience that this was a simple crime of opportunity," said FBI special Agent J.J. Klaver. "It also seems unlikely, although not impossible, that one person acting alone could pull this off so successfully."
But with no forensic evidence and few clues, authorities have struggled to piece together what happened to the on-again, off-again couple.
"It is a true cold case,” he said. “There is no crime scene. That is part of the problem.”
Who are they protecting? A murderer? Somebody knows something. Marge Petrone, mother of missing Philly man Richard Petrone Jr.
“We feel confident that somebody knows something about this that they have never shared with anybody,” he said. “We are looking to shake the trees a bit.”
"Who are they protecting? A murderer?" asked Marge Petrone, Richard’s mother. "Somebody knows something....I don’t know what the loyalties are, but I’m hoping after all this time the loyalties have changed." Marge attended the Thursday announcement. Relatives of Danielle were invited, but were unable to be there, Zajac said.
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"Anytime there is more than one person involved, you have a possible weak link in the conspiracy," he said.
The initiative helps FBI agent Vito Roselli, who has been the lead investigator on the case for many years. Additional agents will review the 10 years worth of information collected by authorities in Pennsylvania and New Jersey. The fresh eyes will hopefully spot new leads in the case, said Klaver, who added the investigators could re-interview people close to Danielle and Richard.
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In the decade since the on-again, off-again couple went missing, rumors swirled. It was a murder-for-hire plot -- Richard had a gambling problem, finally owing the wrong person money or perhaps Danielle’s husband upset over his impending divorce, hired a hit man. Occasionally, less plausible scenarios surfaced – the reunited couple ran off to start a new life, leaving behind Richard’s 14-year-old daughter and Danielle’s 18-month-old son.
Some speculated they were killed in a car crash, the truck ending up submerged in water.
"Given the logical route they would have taken from South Phily to Mount Laurel," Zajac said, "It is very unlikely that this would be some sort of accident."
Investigators found nothing to indicate the pair would have been specifically targeted or that they would have disappeared on their own. Danielle’s estranged husband, Joseph Imbo, has been questioned many times. He was never named a person of interest, although authorities say no one has been ruled out as a suspect.
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"There are a lot of theories, but no a lot of them are supported by forensic evidence or other facts that have developed in the course of the 10 years," Klaver said.
Is it possible? At this point anything is possible. J.J. Klaver, FBI special agent
Both victims’ families openly state they believe Richard and Danielle were murdered.
"Is it possible? At this point anything is possible," he said. "There is nothing that really points overwhelmingly in any one direction or another." Unable to firmly state a possible motive, authorities try to strike possibilities from the list.
The Citizens Crime Commission’s $50,000 reward for information leading to their whereabouts still stands. The public can call 215-546-TIPS.
Contact Alison Burdo at 610.668.5635, firstname.lastname@example.org or follow @NewsBurd on Twitter.