The parents of a U.S. college student who vanished almost two weeks ago in the resort town of Punta Cana have asked authorities to declare her legally dead.

In a letter to Dominican police dated Monday, Subbarayudu and Sreedevi Konanki state that after an extensive search, local authorities believe that Sudiksha, a 20-year-old student at the University of Pittsburgh, drowned.

“Initiating this process will allow our family to begin the grieving process and address matters related to her absence,” they wrote. “While no declaration can truly ease our grief, we trust that this step will bring some closure and enable us to honor her memory.”

A police official not authorized to speak about the case confirmed Tuesday that authorities received the letter.

Sudiksha Konanki and five female friends had traveled to the Caribbean nation on March 3 for spring break. Police said she disappeared at a beach by her hotel before dawn on March 6.

Authorities have interviewed people who were with Konanki before she vanished, including Joshua Riibe, a senior at St. Cloud University in Minnesota.

Riibe has been detained by Dominican police and is believed to be the last person to see Konanki. He has not been named as a suspect.

He is scheduled to appear in court Tuesday afternoon following a request from his attorney that he be released.

According to the transcript of an interview with prosecutors, reported by Dominican media as well as NBC and Telemundo, Riibe told police he was drinking with Konanki on the beach and they were kissing in the ocean when they got caught in a current. Riibe said he was a former lifeguard and helped bring her ashore.

He told investigators he vomited upon reaching the beach and that Konanki said she was going to fetch her things. When he looked up, she was gone. He said he was later surprised to hear of her disappearance.

In their letter, the Konankis wrote that “the individual” last seen with their daughter is cooperating and that no evidence of foul play has been found.

Sudiksha Konanki was born in India and later became a U.S. permanent resident.