A distress signal was received at 05:30 local time (03:30 GMT) from the Sea Story, which left port near Marsa Alam on Saturday for a five-day diving trip with 31 tourists and 14 crew, according to the governor of Red Sea province.
Maj-Gen Amr Hanafi said the survivors were found in the Wadi el-Gemal area, which is south of Marsa Alam, and that they were receiving the necessary medical care.
He added that the Egyptian Navy warship El Fateh and military aircraft were intensifying their efforts to locate the missing.
Marsa Alam is a popular destination for tourists on Egypt’s southern Red Sea coast and is surrounded by diving spots, including renowned coral reefs.
There was no immediate comment from Sea Story's Egypt-based owner and operator, Dive Pro Liveaboard.
But its website says the vessel was built in 2022 and is 44m (144ft) long. It has four decks and 18 cabins that can accommodate up to 36 passengers.
AzVision.az