Parents of Pitt student who went missing while on spring break ask to have daughter declared dead

The family of Sudiksha Konanki, the University of Pittsburgh student who vanished while on spring break, has formally requested that the Dominican police declare their daughter deceased, according to ABC News.

Authorities have said they believe Konanki died by drowning in the early hours of March 6, officials told ABC News.

Konanki's parents say they trust the investigation and acknowledge that there is no evidence of foul play.

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Her parents added that Joshua Riibe -- a Minnesota college student who was swimming in the ocean with Konanki the night she went missing -- is cooperating with the investigation and they acknowledge there is no evidence of foul play, the sources said.

The parents said they understand certain legal procedures must be followed for their request, but they are prepared to comply with any necessary formalities or documentation, according to sources.

Meanwhile, the 22-year-old Riibe -- who has not been charged with a crime -- has been questioned by prosecutors over three days, an official close to the investigation told ABC News.

His lawyers have requested a habeas corpus hearing because they believe he's being detained illegally and want to prevent him from being placed in custody, a source from the Dominican Republic Ministry of Justice told ABC News.

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Authorities have confiscated Riibe's passport and his attorneys said he's being surveilled at his hotel.

In the Dominican Republic, people can challenge an unlawful detention through a habeas corpus hearing. Detained individuals are required to be brought before a judge within 48 hours, or they must be either charged or released.

A ruling on the habeas corpus hearing request cannot prevent an order of arrest by Dominican authorities, according to Riibe's lawyer and a source from the Dominican Republic Ministry of Justice.

Konanki's missing persons case is being treated as an accident, sources said. Authorities said Riibe is not a suspect and is cooperating and being questioned as a witness.