Search warrant for Brian Laundrie: Gabby Petito’s mom says conversations and texts with her appeared to show ‘more and more tension’ between couple

• A Florida search warrant references Gabby Petito's mother's characterizations of their calls and texts.
• Her mom believed there was "more and more tension," between Petito and Laundrie, according to the warrant.
• On Monday, the FBI also executed a search warrant at Laundrie's home, declaring it a crime scene.
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A search warrant filed last week by Florida law enforcement to search Brian Laundrie's computer referenced the appearance of "more and more tension," between Gabby Petito and Laundrie in texts and phone conversations between Petito and her mother Nichole Schmidt.

"During the trip, the subject sent multiple text messages and had many talks with her mother, Nichole Schmidt, via cellphone communication," the warrant stated. "During these conversations there appeared to be more and more tension between her and Laundrie."

The warrant was filed by North Port Police Department after Laundrie was named a person of interest last week in the late August disappearance of his 22-year-old fiancée Gabby Petito, as they embarked on a cross-country road trip.

The Florida police warrant also adds that Schmidt said that she received "odd texts" from Petito, including the last one sent on August 27, where Petito referred to her grandfather by his first name, Stan, which was unusual to her mother and cause for concern that someone else may have been using Petito's phone.

The tenor of the messages, and later, the lack of communication from Petito is what led her mother to reach out to authorities, according to the warrant.

The warrant was filed in order to gain access to Laundrie's computer and electronic devices.

Separately on Monday, the FBI executed a court-obtained search warrant at Laundrie's family's home in North Port, Florida, declaring the location a crime scene.

"The FBI is executing a court-authorized search warrant today at the Laundrie residence in North Port, FL relevant to the Gabrielle "Gabby" Petito investigation," the FBI's Tampa office said in a tweet.

Laundrie's family home was declared a crime scene a day after a body that could be Petito, was found in Grand Teton National Park, Wyoming. An autopsy will be completed on Tuesday, September 21, to determine if it is Petito.