Twenty Years On, This US Couple's Disappearance Is Still A Mystery

Twenty years ago, on a Saturday night, Richard Petrone Jr and his girlfriend Danielle Imbo, accompanied by their friends, went out to a bar in Philadelphia. Once the outing was over, Mr Petrone Jr was supposed to drop Ms Imbo off at her home in New Jersey and head back to his apartment in Philadelphia. Their friends or anyone else never heard back from them after they left the bar, CNN reported.

Investigators found no forensic evidence of the couple's whereabouts after they were last seen at the bar, retired FBI special agent Vito Roselli, who was the case's first lead investigator, said.

Their truck was not spotted on any of the area's toll bridge cameras and the couple's credit cards and bank accounts registered no activity, he added.

The couple, along with Mr Petrone Jr's 2001 black Dodge Dakota pick-up truck, just disappeared into the night. 

His mother Marge Petrone said she knew something was wrong when she didn't immediately hear back from him. "His phone was never off - it was always in his hands," she told CNN.

To this day, there are no leads in the case. No one in the family thinks the couple planned their disappearance and relocated to a different area to start a new life. At the time, they were parents to a teen and a toddler, respectively. According to their families, they would never just abandon their kids.

Mr Roselli, who now works in cybersecurity for an international company in Miami, says, "It stays with me. Like, 'What did I miss?' ... is constantly living rent-free in my head. But also because you want to see closure for the two families."

FBI's Philadelphia office says the matter remains a top priority. According to one of the statements, following the couple's disappearance, the FBI collaborated with law enforcement from other jurisdictions in New York, New Jersey, and Pennsylvania.

They dispatched divers to investigate the Delaware River and other bodies of water between Philadelphia and Mount Laurel. Investigators followed leads in many states and examined financial, phone, and road toll data. They also looked into a flurry of theories, but nothing brought any fruitful results. 

Technology was less developed in the early 2000s than it is now, which limited the scope of the investigation. While forensic science has advanced much since then, in this instance, it hasn't had much of an impact, as there is no physical evidence.

The FBI is offering a reward of up to $15,000 for information leading to the arrest and conviction of anyone involved in the case.