Sept. 15 update: Police have now named Gabby Petito’s fiancé a ‘person of interest’ in her disappearance.

NORTH PORT, Fla. (WFLA) — The family of a missing North Port woman issued a new statement Tuesday asking for her fiancé to cooperate with the investigation into her disappearance.

Gabby Petito, 22, went missing during a cross-country trip with her fiancé in her van. Her family believes that she was last seen with him in the Grand Teton-Yellowstone area.

The Schmidt and Petito families released a joint statement Tuesday afternoon saying that Petito’s fiancé “refuses to help.” In their statement, the families say he should not “remain in the background” as several agencies, including the FBI and North Port police, continue searching for her.

“The Schmidt and Petito family are going through the worst moments of their lives,” the families said in their statement. “Their beautiful twenty-two year old daughter is missing and the one person that can help find Gabby refuses to help.”

An attorney for the family of the fiancé released a statement earlier Tuesday saying the family would be “remaining in the background at this juncture and will have no further comment.”

In the statement released by the Schmidt and Petito families, they say the search is being hampered by the fiancé’s refusal to answer questions.

“[He] is refusing to tell Gabby’s family where he last saw her. [He] is also refusing to explain why he left Gabby all alone and drove her van to Florida,” the statement said. “These are critical questions that require immediate answers.”

The families also ask him to at least let them know if the search is in the right area.

According to the statement released on behalf of the fiancé’s family, they were aware of the search around Grand Teton National Park in Wyoming.

“On behalf of the… family, it is our hope that the search for Miss Petito is successful and that Miss Petito is reunited with her family,” the statement said.