Joshua Riibe, the last person seen with missing University of Pittsburgh student Sudiksha Konanki, had his passport confiscated by Dominican Republic authorities as part of an ongoing investigation into her disappearance.

An American linked to the disappearance of a University of Pittsburgh student was spotted by NBC News with investigators and his attorney on a beach in Punta Cana early Sunday. Joshua Riibe was seen pointing toward the sea while a group of security officials kept people away from the area.

The search for a U.S. college student who went missing in the Dominican Republic intensified on Monday after a man questioned by authorities visited the beach where she was last seen and spoke with officials.