Police were back out at a Florida reserve Thursday to search for Brian Laundrie.

Law enforcement were back at the Carlton Reserve for the first time in several days.

Police requested the assistance of a cadaver dog to assist in the search as the 23-year-old has now been missing for over a month.

Laundrie’s parents told law enforcement the last time they saw their son was Sept. 13.

The 23-year-old is the sole person of interest in the disappearance and death of his fiancé Gabby Petito.

Chris and Roberta Laundrie say their son told them he was going for a hike in the 25,000-acre reserve but never came home.

Investors have been scouring the alligator- and snake-infested terrain since he went missing.

Petito’s remains were found near Wyoming’s Grand Teton National Park Sept. 19.

On Tuesday, the Teton County coroner’s office announced that Petito died of strangulation, but did not offer any information on a possible suspect.

Petito’s family is reportedly in Wyoming to collect her remains.

A foundation started in Petito’s honor is hosting its first fundraiser this Sunday in Patchogue.