They scrambled to the River Foyle after the alarm was raised just after midnight.
FSR say: “At 00:12 a.m. on Tuesday the 18/6/19 Foyle Search & Rescues Pager Team were tasked by the PSNI to reports of a person observed on the wrong side of the railings.
“As Pager teams responded the person was further reported as having entered the water, Boat crews arrived on scene within minutes & guided by land crew located the person commencing a successful rescue.
“The person was removed to FSRs base at Prehen where an EMT & Emergency First Responders, assessed & treated the person for cold water shock & early onset hypothermia.
“The patient was then transferred into the care of NIAS Paramedics and transported to Hospital.
“Appreciation to the members of the Public who deployed the Lifering, CCTV & PSNI.”