North Port police are admitting that they lost track of Brian Laundrie after they confused him for his mother in surveillance video.

Josh Taylor, spokesperson for the North Port Police Department, says police started tracking Laundrie after Gabby Petito's family reported her missing on Sept. 11.

Police watched Laundrie leave in his vehicle on Sept. 13 and believed he came back on Sept. 15.

On Sept. 16, North Port Police Chief Todd Garrison said that they knew where Laundrie was.

However, the next day Laundrie's family reported him missing.

"That was certainly news to us that they had not seen him," Taylor says. "We thought that we had seen Brian initially come back into that home on that Wednesday."

He says they believe they saw his mother wearing a baseball cap and thought it was Laundrie.

He admits it was a costly mistake.

"No case is perfect," Taylor says.

Laundrie's remains were found last week in a Florida nature reserve. He was the only person of interest in the murder of Petito.