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NORTH PORT, Fla. (WFLA) — There was a large law enforcement presence on Friday at the Sarasota County nature reserve where the search for Brian Laundrie has been focused.

One of the entrances to the Myakkahatchee Creek Environmental Park, which gives access to the Carlton Reserve, was taped off Friday morning. Later, in the afternoon, officers were seen carrying large rifles into a wooded area about a mile from the entrance of the reserve off of Tropicaire Boulevard.

When WFLA’s Allyson Henning reached out to North Port police about those officers, a spokesperson told her the group was there “training and searching.”

Earlier Friday, yellow “POLICE LINE DO NOT CROSS” tape went up at the entrance to the reserve. It was the first time we’ve seen police tape up in the area since the search for Laundrie started.

A North Port police SUV was seen just beyond the tape. Several other law enforcement vehicles were in the park but obscured by trees.

Friday’s law enforcement activity comes after several crews, including a human remains detection K9 team from Pasco County, searched the Carlton Reserve on Thursday. The Pasco County units were not at the scene on Friday, a spokesperson confirmed.

This week officially marked one month since Laundrie’s parents said they last saw him. Laundrie was reported missing by his family on Friday, Sept. 17. At the time, they told police they had last seen him leave home to go to the Carlton Reserve area for a hike on Tuesday, Sept. 14. The family’s attorney, Steve Bertolino, later said that, after further communication with the FBI, the Laundries now believe their son left home to go hiking on Sept. 13.

The day before he was reported missing, Laundrie was named a person of interest in the disappearance of Gabby Petito. The couple had been on a months-long cross-country road trip together before Laundrie returned home to North Port without her on Sept. 1, according to police.

Petito was reported missing on Sept. 11. Her body was found in Wyoming on Sept. 19 and, two days later, her death was ruled a homicide.

The Teton County coroner announced this week Petito’s cause of death was manual strangulation or throttling.

“Manual strangulation or throttling is strangulation by use of hands as opposed to mechanical strangulation,” Dr. Brent Blue told 8 On Your Side’s Mahsa Saeidi.

The coroner’s finding determined she was likely dead for three to four weeks before her body was found.

Laundrie remains the lone person of interest in the Petito investigation. A federal arrest warrant was issued for Laundrie last month for “use of unauthorized access devices” – a Capital One Bank debit card and a personal ID number for two Capital One Bank accounts – following Petito’s death.