The last known photo of an Air Force veteran who vanished in South Florida last week was released Monday and appeared to show Tricia Todd, 30, "in good spirits," Martin County Sheriff William Snyder said.
During a news conference, authorities said the image was taken by a surveillance camera at a grocery store in Hobe Sound, Fla., on Tuesday night, just a few hours before she disappeared.
Todd failed to pick up her 2-year-old daughter the next morning from a hospital, where the girl had been taken by her father, Todd's ex-husband, Snyder said.
Detectives later found Todd's car near her Hobe Sound home with the keys still in the ignition and her cell phone gone.
"As of this moment, we've forensically examined her car, her home, her former husband's car," Snyder said. "There is not one scintilla of evidence of a crime."
Todd's ex-husband lives in North Carolina but was in Florida for a visit with their daughter, Snyder said.
Snyder said that the ex was the alleged offender in a domestic violence incident against Todd two years ago, but that he was not arrested.
"We don't know the nature of" the allegation, he said, adding that the ex-husband has cooperated with authorities in Todd's disappearance.
"Every single thing he's told us so far has been corroborated," Snyder said.
Snyder said that Todd's social media presence left an impression that she was "having some kind of emotional angst within herself," though he did not provide additional details and, when asked if she had sought counseling or medical attention, he said: "I don't know the answer to that."
Volunteers helped authorities as they searched for Todd over the weekend. That search, which the sheriff's office described as "full scale," included helicopters, marine units, bloodhounds and ATVs, which were used in state parks, beaches and woods where Todd was known to take early morning walks.
Synder said Monday that authorities planned to continue their search. The sheriff's office had so far received 15 to 20 tips about Todd, including possible sightings, Snyder said, but that none had yielded her whereabouts.