Crews continue searching for Brian Laundrie at Florida nature preserve

NORTH PORT, Fla. — Authorities have returned to a nature preserve in Sarasota County for a second straight day as they continue to look for clues in the disappearance of a Florida man deemed a person of interest in the homicide of his girlfriend.

Police and other agencies are scouring the Carlton Reserve in search of Brian Laundrie, who has not been seen in more than a week.

Officials said they are using ATVs, dogs, dive teams, boats and sonar equipment to analyze large bodies of water amid the swampy terrain.

Investigators said nearly 75 percent of the reserve is underwater.

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"We are trying to cover every acre in this preserve," said North Port police commander Joe Fussell.

The parents of Brian Laundrie are not a part of the search and remain presumably in their home Wednesday.

Neighbors said they are keeping an eye out for any signs of Laundrie on their property.

Remains of his girlfriend, Gabby Petito, 22, were found in Wyoming on Sunday and positively identified by a coroner on Tuesday, according to the FBI.

Officials are calling her death a homicide and continue to ask the public for tips in the case.

Petito, 22, and Laundrie set out on a cross-country road trip this summer.

Laundrie returned to their home in North Port, Florida, on Sept. 1, but without Petito, causing her parents to file a missing person's report on Sept. 11.

The reserve became the primary site for the search when Laundrie's parents said they hadn't seen him since Sept. 14.

Apparently, his parents believe he came to the 25,000-acre Florida nature preserve to hike.

Close to a dozen agencies are conducting the search for Laundrie, including the North Port Police Department, the FBI, the Florida Wildlife Commission, sheriff's offices in Sarasota, Lee and Charlotte counties along with police departments in Sarasota and Venice.

The Lee County Sheriff's Office provided high-altitude drones that have more advanced technology that allows investigators to see crisp images in real-time.

Officials said Tuesday's search of the wildlife reserve did not turn up any clues.