The search continued Sunday for two soldiers who are missing in the surf off Port St Johns.
The SANDF members, who were off-duty Saturday when they went swimming, were taking part in military exercises in the area.
NSRI spokesperson, Craig Lambinon, said the Port St John's station was activated at 15h20 Saturday.
"The sea rescue craft Freemasons Way was launched and an extensive sea search for two male military members who were reported to have gone missing in the surf was conducted.
The SA Police Services were also activated," said Lambinon.
"It appears that while swimming one man got into difficulty in the surf and according to reports a man went into the surf to attempt to assist but he too got into difficulty and eye-witnesses reported both men disappeared under water. Both men are believed to be SA National Defence Force (SANDF) members, one is from Pretoria and one is from Oudtshoorn, and they were off duty at the time from military exercises that are taking place in the area".
"Despite an extensive sea and shoreline search no sign of the men has been found and they are missing a feared to have drowned," Lambinon said.
"An SA Air Force helicopter conducted a night search and continued a search from first light today (Sunday, 17th April), together with the SA Police Services, EC Government Health EMS, SANDF members and a Police Dive Unit and an ongoing search will continue. NSRI Port St Johns remain on alert to assist if necessary," he added.
Police are investigating and an ongoing search is being carried out.