PUNTA CANA, Dominican Republic — Authorities in the Dominican Republic have seized the passport of Joshua Riibe, the man last seen with missing University of Pittsburgh student Sudiksha Konanki, Fox News has learned.

Riibe’s attorneys said Saturday that Riibe’s travel document was taken by authorities “several days ago.” He has not been named a suspect in the 20-year-old student’s disappearance, but authorities have said he is a “person of interest” in the matter, which they consider a missing person case.

“It was confiscated by authorities when he tried to check out several days ago, when the investigation began,” lawyers from Guzmán Ariza, a Dominican Republican law firm, said. “He hasn’t had access to it since then.” 

Though Riibe, who is from Rock Rapids, Iowa, and is a senior at St. Cloud State University in Minnesota, has not been accused of any crime, the 22-year-old has been intensely scrutinized since Konanki’s disappearance on Mar. 6. A source close to the investigation told Fox News Digital Friday that Riibe, the only publicly known eyewitness, is considered a “key element in the investigation.” 

Riibe’s parents, Albert and Tina Riibe, have denounced the investigation of their son, saying that he has “been detained under irregular conditions and subjected to extensive questioning without the presence of official translators or legal counsel until Wednesday, March 12.”

“He has remained in his hotel room under police surveillance and has been repeatedly taken to the police station since March 6, where he has been interrogated for long hours,” the statement, shared through the Riibes’ attorneys, said. “This situation has raised serious concern within his family, which has led us to retain legal counsel to initiate legal actions ensuring his safety and the protection of his rights throughout this process.”

Riibe has reportedly told varying stories about Konanki’s disappearance to local authorities. According to local outlet Noticias SIN, Riibe told police that he went swimming with Konanki but left after falling ill from the waves, leaving Konanki in the water.

Sudiksha Konanki appears in an undated photo on her TikTok profile. She was last seen on Mar. 6 at a resort beach in Punta Cana. (@sudikshakonanki/TikTok)

In a second version of the story, he reportedly said that he left Konanki in knee-deep water before he passed out sick on the beach. In a third story, Riibe said he saw Konanki walking on the beach before he fell asleep.

Fox News Digital’s Bryan Llenas, Audrey Conklin and Michael Ruiz contributed to this report.