A Los Angeles Fire Department firefighter who has been missing for nearly two weeks is likely the victim of a "violent kidnapping," according to the head prosecutor of Baja California, Mexico. Frank Aguilar, 48, was last heard from on the night of Aug. 20, when he went down to check on the condo the family rents out through Airbnb, according to his two daughters. The property is located in the coastal city of Rosarito, less than 20 miles south of the U.S. border. Aguilar traveled alone and was only expected to be there for a few days, they said. The FBI got involved in his disappearance six days later. Investigators in Baja California say there were signs of violence at the condo. "We are working with technical personnel to establish his last instance when his freedom was taken," Hiram Sanchez, the head prosecutor, said. "We have found a lot of evidence that leads us to believe this was an act of violence, nevertheless we have not determined for sure this is what happened to him."