Joshua Riibe, believed to be the last person to see Sudiksha Konanki before she vanished in Punta Cana, said he's trying to 'help' investigators as he warned 'the ocean is a dangerous place'

Joshua Riibe is believed to be the last person to have seen University of Pittsburgh student Sudiksha Konanki before she went missing nearly 10 days ago.

An American linked to the disappearance of a University of Pittsburgh student was spotted by NBC News with investigators, his father 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 man identified as a person of interest in the case of missing University of Pittsburgh student Sudiksha Konanki, who disappeared while on vacation in the Dominican Republic, was seen on the beach with investigators early Sunday morning.