India, March 11 -- The father of 20-year-old Sudiksha Konanki, a University of Pittsburgh student who went missing in the Dominican Republic, has urged authorities to expand their investigation as the search enters its fourth day.

"It's four days, and if she was in water, she would likely have been strewn to shore," her father, Subbarayudu Konanki, told WTOP-FM. "She's not found, so we're asking them to investigate multiple options, like kidnapping or abduction."

Sudiksha Konanki was last seen before dawn on March 6 near a beach close to the resort where she was staying with friends, according to Civil Defense officials.

Authorities have deployed drones, helicopters, and detection dogs to search the waters off the island's east coast, ...