New Delhi, March 14 -- Chilling new surveillance footage has surfaced, showing missing University of Pittsburgh student Sudiksha Konanki staggering while walking arm-in-arm with Joshua Steven Riibe, an Iowa man identified as a "person of interest" in her disappearance. The footage, recorded around 4:15 a.m. near the beach at Punta Cana's Riu Republica Hotel, shows the pair holding hands while Konanki's friends stroll nearby.

Riibe, wearing a muscle shirt, is seen holding out his phone, seemingly taking selfies as the pair struggles to walk straight. According to Dominican Republic authorities, the two were last seen together after leaving a nightclub following a power outage at the resort.

Riibe, a 22-year-old Minnesota college student,...