"About 10 minutes later, we heard a second explosion on the Energos Winter," he said. "The second explosion was much larger and a much bigger fire erupted." Advertisement AdvertisementAdvertisement AdvertisementAccording to one officer, the second explosion was at a connection point between both vessels. Neither captain initially realised that the fires had been caused by a drone strike. The drone strike is similar to others that have hit Cairo's Gulf and Arab allies throughout the US-Israeli war against Iran, but is unprecedented in Egypt.