Two US navy pilots were shot down over the Red Sea on Sunday in an apparent case of friendly fire, the US military said, marking the most serious incident to threaten troops in more than a year of the country targeting Yemens Houthis.Both pilots were rescued alive after ejecting from their stricken aircraft, with one suffering minor injuries. But the incident underlines just how dangerous the Red Sea corridor has become amid the ongoing attacks on shipping by the Iranian-backed Houthis despite US and European military coalitions patrolling the area.The US military had conducted airstrikes targeting Yemens Houthi at the time, though the militarys Central Command (Centcom) did not elaborate on what their mission was.The F/A-18 shot down had just flown off the deck of the USS Harry S Truman aircraft carrier, Centcom said. On 15 December Centcom acknowledged the Truman had entered the Middle East, but hadnt specified that the carrier and its battle group was in the Red Sea.The guided missile cruiser USS Gettysburg, which is part of the USS Harry S Truman Carrier Strike Group, mistakenly fired on and hit the F/A-18, Centcom said in a statement. The incident was being investigated.From the militarys description, the aircraft shot down was a two-seat F/A-18 Super Hornet fighter jet assigned to the Red Rippers of strike fighter quadron 11 out of Naval Air Station Oceana in Virginia.It wasnt immediately clear how the Gettysburg could mistake an F/A-18 for an enemy aircraft or missile, particularly as ships in a battle group remain linked by both radar and radio communication.However, Centcom said that warships and aircraft earlier shot down multiple Houthi drones and an anti-ship cruise missile launched by the rebels. Incoming hostile fire from the Houthis has given sailors just seconds to make decisions in the past.Since the Trumans arrival, the US has stepped up its airstrikes targeting the Houthis and their missile fire into the Red Sea and the surrounding area. However, the presence of an American warship group may spark renewed attacks from the rebels, like what the USS Dwight D Eisenhower saw earlier this year. That deployment marked what the navy described as its most intense combat since the second world war.On Saturday night and early Sunday, US warplanes conducted airstrikes that shook Sanaa, the capital of Yemen, which the Houthis have held since 2014. Centcom described the strikes as targeting a missile storage facility and a command-and-control facility.Houthi-controlled media reported strikes in both Sanaa and around the port city of Hodeida, without providing any casualty or damage information. In Sanaa, strikes appeared particularly targeted at a mountainside known to be home to military installations. The Houthis later acknowledged the aircraft being shot down in the Red Sea.The Houthis have targeted about 100 merchant vessels with missiles and drones since the Israel-Hamas war in the Gaza Strip started in October 2023.The Houthis have seized one vessel and sunk two in a campaign that has also killed four sailors. Other missiles and drones have either been intercepted by separate US- and European-led coalitions in the Red Sea or failed to reach their targets, which have also included western military vessels.The rebels maintain that they target ships linked to Israel, the US or the UK to force an end to Israels campaign against Hamas in Gaza. However, many of the ships attacked have little or no connection to the conflict, including some bound for Iran.The Houthis also have increasingly targeted Israel itself with drones and missiles, resulting in retaliatory Israeli airstrikes.