Bombing of Bahrain in World War II
On 10 June 1940, the Kingdom of Italy declared war on the French Republic and the United Kingdom. The Italian invasion of France was short-lived and the French signed an armistice with the Italians on 25 June, three days after France's armistice with Germany. This left the British and the forces of the Commonwealth of Nations for the Italians to contend with in the Middle East.
Bahrain (and Dhahran, Saudi Arabia) 
Early on October 19, 1940, four Italian SM.82s bombers attacked American-operated oil refineries in the British Protectorate of Bahrain, damaging the local refineries The raid also struck Dhahran in Saudi Arabia, but causing little damage.
Indeed in order to strike the British-controlled oil refineries at Manama in the Persian Gulf, these SM82s bombers undertook a flight of 4,200 km (2,610 mi), lasting 15 hours at 270 km/h (170 mph), that was for the time arguably a record for a bombing mission. Each aircraft carried a load of 1,500 kg (3,310 lb). This long-range action was successful, taking the target totally by surprise, and the SM.82s landed without problems at Zula. The raid caused the Allies some concerns, forcing them to upgrade their defences. This, more than the limited amount of damage caused, further stretched Allied military resources.
The Italian Command intended to employ the special SM82s to bomb the English oil plants of Manama, in the Persian Gulf, in order to show the potential ability of the Italian air force. It was a long and difficult mission involving a 4,000 kilometre flight. Ettore Muti and his comrades spent four days working on a complete revision of the plans and established a complex flight plan....On December 18, at 5.10 pm, after filling both the normal and the supplementary tanks, they loaded three out of four SM82s with 1.5 tons of incendiary and explosive bombs weighing 15, 20 or 50 kilograms. Then the four three-engine bombers took off.In command of the first aircraft, which gained height with difficulty from the Rhodes- Gadurrà runway because it was overloaded with 19,500 kilograms, was Lieutenant Colonel Muti. He was assisted by Major Giovanni Raina and by Captain Paolo Moci, who had previous experience in flying planes overloaded up to 21 tons.....The SM82s, after gaining height (a manoeuvre which took remarkable efforts because of the enormous weight of the aircrafts) headed east, flying over Cyprus, Lebanon and Syria, bending to the southeast as they went past Jordan and Iraq until they reached the Persian Gulf. During the very long outward flight, the role of Muti's SM82 pathfinder proved its essential function in leading the squadron..... At 2.20 am, just before reaching the Bahrain Islands, Lieutenant Colonel Federici's aircraft suddenly lost sight contact with Muti's SM82 and had to drop its bombs on different targets in the vicinity of Manama, while the other planes hit the fixed target.As bombardier Raina later told "the operation of spotting the target was easy thanks to the total illumination of the extractive and refinery plants" which were partially damaged by the bombs (half a dozen wells and some oil deposits were set on fire). As soon as they perceived the glares of the first explosions, the Italian planes made off along the escape route landing to the Zula runway (Eritrea) at 8 8:40.The whole Italian formation had flown 2,400 kilometres in 15.30 hours. At the Eritrean airport, along with a small crowd of Italian aviators, the brave pilots found the fourth SM82 squadron which, in the meantime, had come from Rhodes as a support plane on the way back, should one of the crafts make an emergency landing in the desert.Alberto Rosselli 
Rome declared that their bombers had set a new distance record, covering 3,000 miles on the outgoing trip from bases in occupied Rhodes. American Magazine "Time" wrote that the Italians insisted that the planes had been refueled from submarine tankers though in actuality, the planes had simply been loaded with fuel.
The Bahrain raid was followed by other long-distance Italian raids in Ethiopia and Eritrea in 1942, and would have been repeated -with a better SM82 bomber- in a raid on New York in summer 1943 (that was not done because of the Italian defeat in September 1943). Even a commercial aerial trip was done between Rome and Tokyo in summer 1942.
See also 
- Lembo, Daniele. SIAI SM.82 Marsupiale. "Aerei Nella Storia", Issue 22. Parma, Italy: West-ward Edizioni, 2002, p. 10-31.