The person of interest in the disappearance of University of Pittsburgh student Sudiksha Konanki claims he saved her from drowning, as police continue to search for clues a week after she vanished during her spring break trip to the Dominican Republic.

Joshua Riibe told law enforcement he and Konanki were both nearly swept away in the ocean as they were wading in the water early on the morning of March 6 … and that he struggled to get them to safety, according to a transcript obtained by Dominican Republic news outlet Noticias SIN.

Once back on land, the 22-year-old student claims he vomited seawater as Sudiksha walked away to get her personal belongings that had been pushed down the beach by waves.

Joshua says he fell asleep on the beach and woke up to being bitten by mosquitoes at sunrise … prompting him to head back to his hotel and hit the hay again.

Sudiksha and Joshua were reportedly both guests at the Riu Republica hotel resort. The college students were both seen together — with Joshua’s arm around Sudiksha — heading to the beach around 4:15 AM. Investigators believe she vanished around 4:50 AM.

Though Joshua is confident he saved her life while they were together … he reportedly refused to answer several key questions from police — saying his lawyers have advised him to keep quiet — according to Noticias SIN.

He declined to answer if he reported their beach scare to authorities, what he’s told his friends about the experience, and how police can verify his answers, among other questions.