Infrared technology used in overnight searches for Gabby Petito's fiancé Brian Laundrie

Authorities have used infrared technology in the ongoing search for Gabby Petito's fiancé Brian Laundrie, according to local reports. Law enforcement is flying overnight, using thermal imaging in hopes of finding the 23-year-old who is a person of interest in the case of Petito, CBS affiliate WTSP reported, citing law enforcement sources. 

The search has been focused in the Carlton Reserve, a 25,000-acre area with hiking trails, swampy terrain and tough-to-reach places in Florida's Sarasota County. The county sheriff's office said Wednesday that divers had responded to the reserve — where Laundrie reportedly went last week — to search bodies of water for any evidence, as part of wider search efforts. 

Laundrie remains missing more than a week after his family said they last saw him. Law enforcement searched Laundrie's home in Florida for eight hours on Monday, questioning his parents and collecting evidence that could tell them what happened to Petito, whose death has been ruled a homicide.