Sen Sgt Maj Boonyarit Inthakarn of the Patong Police was called to the beach at about 2:10pm.
Thanakit Srisuwanwichian, 21, explained to the officers that he and his friend Akkarapol Pattranonwere swimming together when they both started being dragged away from the shore.
Thanakit explained that he managed to make it back to the beach, but his friend Akkarapol was dragged far away from the shore.
Beach vendor Supakit Thongplang wa salso on hand, explaining to the officers that he helped Thanakit to return to safety, but was unable to help Akkarapol.
A search team on jet-skis from Patong and Karon have been scouring the waters since then to find Akkarapol.
So far he has not been found.