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.

A key witness, who has been identified as a person of interest by the Loudon County Sheriff’s Office in the U.S. investigation of Sudiksha Konanki, shared insight into his evening with her.

The Dominican Republic authorities grilling Iowa man Joshua Riibe into the early morning hours Sunday as the mysterious disappearance of 20-year-old S

Newly emerged footage shows missing University of Pittsburgh student Sudiksha Konanki and the person of interest in her case at an outdoor bar before she disappeared from a Punta Cana beach earlier this month.

Joshua Riibe, the person of interest in Sudiksha Konanki's March 6 disappearance in the Dominican Republic, has spoken out for the first time, stating that he is 'just trying to help.'

A person of interest has been identified in the disappearance of Sudiksha Konanki, a University of Pittsburgh student who vanished while on spring break in the Dominican Republic last week.

Joshua Riibe, a 24-year-old tourist from Iowa, has come under the spotlight, with investigators naming him a 'person of interest.'

Joshua Riibe was interrogated by Dominican Attorney General Yeni Berenice Reynoso and Navy Vice Admiral Agustin Morillo Rodriguez until nearly 3 am on March 16.

Authorities say the man isn't a suspect but he may have been the last to see the University of Pittsburgh student.