Authorities investigating the disappearance of Stacy Peterson — the missing fourth wife of police officer Drew Peterson — are chasing down a new lead involving truckers.

As the ENQUIRER reports in this week’s issue, police believe Drew Peterson strangled his pretty young wife Stacy in the bedroom of their home and then stuffed her body in a barrel after he discovered sexual messages that she’d exchanged with another man.

On Saturday, Illinois State Police revealed that two truck drivers in Bolingbrook, Ill. were at a truck stop on Oct. 29 at around 3:30 a.m. when they were approached by two men — one of whom was believed to be Drew Peterson.

The men asked the truck drivers to "transport a package to an undisclosed location," Trooper Mark Dorencz said in a statement. After reaching the location, the men would "regain possession of the package and continue transporting it to a location not accessible by semi-trailers."

While Drew has denied any involvement in Stacy’s disappearance (he said he believes she ran off with another man), authorities have called the case a possible homicide and are investigating the death of his third wife, Kathleen Savio, who was found dead in a bathtub in 2004.

For all the details on the police case against Drew Peterson, pick up the ENQUIRER on newsstands now!