KARACHI — A cargo plane carrying five crew members went missing off the coast of Karachi on Tuesday night, prompting Pakistani authorities to launch a search and rescue operation, aviation officials said. The Boeing 737 rapidly descended and lost contact with air traffic controllers after reporting a navigational system problem at 21:21 local time (16:21 GMT) on Tuesday, Pakistan's airport authority said. The plane had been en route to Karachi from Sharjah in the United Arab Emirates.The plane was operated by K2 Airways, a private cargo airline based in Karachi. The company was founded in 2018, according to its website.In a statement on Wednesday, K2 Airways identified the five crew members on board the aircraft, and said it was "fully cooperating with the Pakistan Civil Aviation Authority and other government agencies"."We continue to pray, earnestly, for the safety of our colleagues," the statement said.According to preliminary data from Flightradar24, a flight-tracking platform, the plane recorded a sharp fluctuation in altitude before a steep descent.The aircraft went missing while flying over the Arabian Sea near Ormara in Pakistan's Balochistan province, local broadcaster Geo News reported.Various agencies, including the navy and air force, have been deployed to look for the missing plane, the airport authority said.The missing aircraft was a Boeing 737-400 and the only aircraft operated by private cargo airline K2 Airways. The carrier brought the aircraft into service in 2024.The aircraft originally entered service as a passenger jet with Russia's Aeroflot in 1999 before it was converted into a freighter in 2012, according to Flightradar24.The last major aviation incident in Pakistan involved a domestic passenger flight in 2020. In that incident, a Pakistan International Airlines plane crashed while approaching Karachi airport, killing all but two of the 99 people on board.