BRIDGEPORT - Police appear to finally have new leads in the search for Jeanette and Jeffery Navin, of Easton, who have been missing since Aug. 4.

Documents obtained by News 12 Connecticut show that police found "suspected physiological fluid on a floor mat" in the couple's truck. The term could apply to one of several bodily fluids like blood, semen or saliva.

Investigators are performing forensics tests on the mat and DNA swabs taken from the Navins' truck.

The investigation appears to be focused on the couple's son, Kyle Navin, after police searched his home twice within a week, but police have not yet revealed what they found there.

Previous search warrants filed in the case detail police interviews with the younger Navin shortly after his parents were reported missing. He told police, according to the documents, that he was the last person to speak with them.

The Navins own J&J Refuse, a garbage collection company in Westport. Their son is listed as J&J's operations director. Relatives reported them missing after Jeffrey Navin missed his usual trash route for two days.

Police also looked at the couple's cellphone records, and say both of their phones were turned off or deactivated on Aug. 4, the same day they were last seen. Their truck was found five days later in a parking lot off of the Merritt Parkway. It was abandoned and had a broken window.

According to the warrants, Kyle Navin told police the couple had visited him at his home the morning they were last seen.

The state's Western District Major Crime Squad took control of the search Wednesday.

Investigators arrived at the home of the couple's son on Aldine Avenue just before 5 p.m. Wednesday. Neighbor Stephen Parisi says he told investigators that he had never seen Navin's parents in the neighborhood. He and other neighbors also say that they haven't seen Kyle Navin and his wife recently, either.

Court records show that the couple was more than $2 million in debt, but family members have maintained that financial troubles are not connected to the Navins' disappearance. 

Court records show the debt was related to a home the Navins owned, and that they were trying to sell their business.

Police say there's been no activity on the Navins' bank accounts since the couple disappeared.