Coleraine coastguard said it has been dealing with a "major incident" off the north coast, after four people got into difficulties in the water.
The coastguard said one person was recovered from the water near Dunluce Castle and Whiterocks Beach. Their condition is unknown.
A second person was rescued after the alarm was raised just after 17:00 BST.
The coastguard said that person suffered minor injuries, while two others were unharmed.
Coastguard teams from Coleraine and Ballycastle attended as well as the coastguard helicopter from Prestwick, Portrush RNLI lifeboats and the Northern Ireland Ambulance Service.