Authorities have ramped up their efforts by air, sea and land to track down the 20-year-old University of Pittsburgh student who went missing six days ago while vacationing in the Dominican Republic resort town of Punta Cana.

New surveillance video surfaced showing what are believed to be the last known images of missing University of Pittsburgh student Sudiksha Konanki before she disappeared.

A 'person of interest' has been named — but no charges have been filed — amid the search for missing college student Sudiksha Konanki, 20, who vanished during a spring break trip to the Dominican Republic.