ST. PETERSBURG, Fla.. -- The search and rescue mission to save two men who were swept away from a chartered yacht excursion is now a recovery operation.

Hillsborough County Sheriff's Office said that it will continue searching for Colorado State student Jie Luo and charter mate Andrew Dillman throughout the weekend until dusk on Sunday. Air and marine units will join the search.

Luo was part of a group of students who chartered a boat on March 14. Luo was struggling with the current around and first mate Dillman jumped in to rescue him. Both were carried out and were not able to return to the yacht.

The U.S. Coast Guard concluded its search operation yesterday without any sign of the missing swimmers.

The recovery effort will be scaled back after Sunday to a search by land and water if Luo and Dillman are not located.