Search for Brian Laundrie continues as authorities comb through swampland

As authorities continue their second week of searching tens of thousands of acres of swampland for Gabby Petito's fiance, Brian Laundrie, they are also seeking out new evidence in the investigation.

FBI agents returned to the Florida home Laundrie shared with his parents Sunday, as seen in video shot by CNN. At least two agents could be seen at the home and one had a bag in his hand.

During the FBI's visit to the family home, "The FBI requested some personal items belonging to Brian Laundrie to assist them with DNA matching and Brian's parents provided the FBI with what they could," the Laundries' lawyer, Steven Bertolino said to multiple news outlets.

CNN reached out to Bertolino but hasn't heard back.

Laundrie's parents told authorities on September 17 that the 23-year-old left their home days earlier with his backpack and said he was headed to the Carlton Reserve. A source close to the family told CNN's Chris Cuomo Laundrie left his parents' home without his cell phone and wallet.