CNN  — 

Police searching for Brian Laundrie have found the remnants of a campsite that appeared to have been recently used at the Florida reserve that has been the focus on efforts to find him, a source close to the family told CNN’s Chris Cuomo on Wednesday.

Earlier, law enforcement had asked his father to show them trails that his son was known to have used, but then told him that because of the discovery, they wanted to search the area alone.

The 24,565 acre Carlton Reserve in Venice is currently closed to visitors.

North Port police told CNN the FBI is the lead in the case and that the North Port Police Department would not be making those decisions or taking those actions.

“The FBI would have to answer if that was true,” said Josh Taylor, spokesperson for the police department.

CNN has reached out to the FBI for comment.

Earlier, Laundrie family attorney Steve Bertolino told CNN that Laundrie’s father was asked to help North Port police search for him Wednesday but police had to postpone.

“Chris Laundrie was asked to assist law enforcement in their search for Brian at the preserve today,” Bertolino said. “Since the preserve has been closed to the public Chris has not been able to look for Brian in the only place Chris and Roberta believe Brian may be. Unfortunately North Port police had to postpone Chris’ involvement but Chris and Roberta are hopeful there will be another opportunity to assist.”

CNN asked Bertolino whether Brian’s parents believe he’s in the reserve or another area. “No, they don’t believe he’s in another area. They believe he is in the preserve,” Bertolino said.

Also Wednesday, the Sarasota County Sheriff’s Office was asked to help in the search for Laundrie at the reserve. Aerial video recorded above the Carlton Reserve showed police vehicles in the area.

Bertolino confirmed to CNN that authorities are communicating with him about any developments.

Police are looking for Laundrie following the death of his fiancee, Gabby Petito, whose remains were found last month in Wyoming after the pair took a cross-country road trip.

Though authorities have not explicitly connected Laundrie to Petito’s death, they’ve been looking for him, in part over a federal arrest warrant accusing him of illegally using another person’s debit card.

North Port police have said Laundrie returned to the couple’s home on his own from their trip on September 1 – roughly 10 days before Petito’s family reported her missing. The white van the couple had been traveling in was later recovered at the home.

More than two weeks later, Laundrie’s parents – who had not been communicating with authorities, other than through their attorney – requested police come to their home where they shared they hadn’t seen their son since September 14.

This week, Bertolino told CNN that upon further communication with the FBI, “we now believe the day Brian left to hike in the preserve was Monday, September 13.”

“The Laundries were basing the date Brian left on their recollection of certain events,” Bertolino said Wednesday. “Upon further communication with the FBI and confirmation of the Mustang being at the Laundrie residence on Wednesday September 15, we now believe the day Brian left to hike in the preserve was Monday September 13.”

North Port police confirmed Wednesday that an abandoned vehicle notice was placed on a Ford Mustang belonging to the Laundrie family outside the Myakkahatchee Creek Environmental Park on September 14.

Myakkahatchee park is an entrance to the Carlton Reserve.

Bertolino told CNN that Laundrie’s father, Chris, went to look for him on the night of September 13 when he didn’t return from the park.

The next day, on September 14, both of Brian’s parents returned to the area to look for Brian and saw the citation on the car, Bertolino said.

The parents returned again the next day, September 15, to retrieve the vehicle.

CNN’s Gregory Lemos contributed to this report.