A legally blind social activist from Detroit has gone missing while vacationing in Peru, spurring an investigation by the U.S. State Department and Peruvian police. >> Read more trending news Carla Valpeoz, 35, has not been seen or heard from since Dec. 12, when she was staying at the Pariwana Hostel in Cusco, the Detroit Free Press reported. She missed her flights home, her phone has been off for days and investigators are looking into her credit card activity. The social worker was in Peru to attend a wedding and planned to stay an two extra weeks to go sightseeing. Carla Valpeoz's brother, Carlos Valpeoz, said his sister met up with a group of other tourists on Dec. 11 and toured the Machu Picchu site with them. The group also visited a hot spring and later went dancing at a club. Police have uncovered surveillance video of Carla Valpeoz entering a taxi and heading to a bus terminal the morning of Dec. 12. It's unknown if she boarded a bus, but the State Department has tracked her to the town of Pisac, about an hour north of Cusco. Carlos Valpeoz said he doesn't suspect anyone in the tourist group had anything to do with his sister's disappearance, as they seem 'extremely concerned' and have been helping him and investigators. Carlos Valpeoz said that while his sister is well-traveled, her family and friends are worried for her because of her sight disability. 'She has extremely low vision. She uses a walking cane when she travels by herself. And she was having some difficulty getting into Machu Picchu based on her disability,' he told WJBK-TV. Carla Valpeoz is 5 feet, 1 inch tall with brown hair and brown eyes. She uses a walking cane when alone. She was last seen traveling with a green backpack.