The tourist boat with 31 tourists and 14 crew members was on a several-day-long diving trip.
According to a government representative in the region, they are searching for 17 people who are missing. 28 people have been rescued so far, including two Norwegians who, according to NRK, are "in good spirits".
Airplanes and naval vessels are reported to be participating in the rescue effort.
The diving boat was supposed to have left the port of Ghalib near Marsa Alam on Sunday for diving at Shaab Sataya, also known as Dolphin Reef. The trip was supposed to end in the larger tourist resort of Hurghada on Friday. But early on Monday, the vessel sent out a distress signal. Then contact was lost and the boat disappeared from radar, according to The Sun.
Egypt's tourist resorts on the Red Sea are popular among Swedish travelers as well.
We have around 500 Swedes in the area right now, but no signs that any of them were on board the vessel, says Adam Györki, Nordic communications manager for Tui.
Neither has Ving got any travelers affected.
The Ministry of Foreign Affairs writes in an email response to TT that they currently have no information about Swedes being on the boat.
