Gabby Petito's boyfriend "has the pieces to the puzzle that we need" to locate the young woman, a Florida police chief said.
Chief Todd Garrison of the North Port Police Department, which is investigating the case, spoke with "Good Morning America."
Petito's boyfriend, Brian Laundrie, has refused to speak to authorities about the 22-year-old woman's disappearance.
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The chief of the Florida police department investigating the disappearance of Gabby Petito during a cross-country van trip says that her boyfriend "has the pieces to the puzzle that we need" to locate the young woman.
"I can't speculate why he's not talking. But he has the pieces to the puzzle that we need to be able to find Gabby," North Port Police Chief Todd Garrison said on ABC's "Good Morning America" Thursday of Petito's boyfriend, Brian Laundrie.
Laundrie has refused to speak to authorities about Petito, despite police and the family of the 22-year-old woman pleading that he help find her.
Petito and Laundrie, 23, set out from New York on a cross-country road trip in a converted camper van on July 2, documenting their travels on social media along the way.
But on September 1, Laundrie returned home to North Port, Florida with the van and without Petito, police have said.
Petito's family reported her missing to New York authorities 10 days later and Petito's last known location is believed to be in Wyoming's Grand Teton National Park.
"Two people went on a trip and one person returned and that one person is not talking to us," Garrison said. "He's got all the answers, so my number one question is, where's Gabby?"
Laundrie was declared a "person of interest" on Wednesday by the North Port Police Department in the case of Petito's disappearance.