Authorities in the Dominican Republic are turning up the heat on the Iowa man who was the last person to see University of Pittsburgh student Sudiksha Konanki before she went missing — grilling him into the early morning hours on Sunday.

The “person of interest” in the disappearance of missing Pitt student Sudiksha Konanki claims he saved them both from drowning before she vanished.

According to a source involved in the investigation, Riibe, a former high school wrestler with a strong build, has been "cooperative" with authorities.