The helicopter ditched a week ago about 280 nautical miles (320 miles, 520 kilometers) from its destination on the Spanish island of Gran Canaria off western Africa's coast after departing from Mauritania.
Spain's Defense Ministry announced Thursday night in tweets that the crew members were found dead inside the helicopter's cabin.
The same day that the helicopter disappeared, the ministry had announced that a Moroccan fishing boat rescued the crew members. A day later, the ministry said it had received incorrect information from Moroccan authorities and that the crew was still missing.
The helicopter was initially found by a Dutch boat and was tethered to its side to try to keep it afloat but it later sank in water about 30 to 40 meters (100 to 130 feet) deep.
Spanish searchers spent days searching until they located the submersed cabin of the helicopter and hoisted it Thursday to the surface.