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.

Although authorities consider Joshua Riibe a “person of interest” in the case, he has not been charged or formally accused of any wrongdoing. However, his passport has been confiscated to prevent him from leaving the country.

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

A person of interest in the case of a missing University of Pittsburgh student broke his silence over the weekend, saying that he is focused on helping authorities in the Dominican Republic locate 20-year-old Sudiksha Konanki.

Joshua Riibe may have been the last person to see the college student before she went missing on March 6 Joshua Riibe is speaking out for the first time since he was named a person of interest in the disappearance of college student Sudiksha Konanki.

Joshua Riibe has been detained "under irregular conditions," according to his family. He has not been named as a suspect.