Air Operations, Aleutians

15 28th Composite Bomb Group B-24s, 16 B-25s, 10 343rd Fighter Group P-38s, and 32 P-40s mount 10 attacks against Kiska.

Air Operations, CBI

• 8 341st Medium Bomb Group B-25s attack rail facilities at Thazi.

Air Operations, Central Pacific

22 307th Heavy Bomb Group B-24s staging through Funafuti Airdrome attack 3 phosphate plants and photograph Nauru Island at noon. 5 B-24s are damaged by Japanese Navy fighters and 1 airman is killed.

Air Operations, Europe

• 36 Venturas bomb the railway yards at Boulogne, shipping at Cherbourg and the power stations at Zeebrugge without a loss.

• 339 aircraft are sent to attack Stettin. Included in the total are 194 Lancasters, 134 Halifaxes and 11 Stirlings.
• This raid on a target more than 600 miles from England proves to be the most successful attack beyond the range of Oboe during the Battle of the Ruhr. Visibility is good and the Pathfinder marking is excellent. 24 fires are still burning when a photographic reconnaissance aircraft flies over Stettin almost 36 hours later.
• 13 Lancasters, 7 Halifaxes and 1 Stirling are lost.
• 86 Stirlings raid the Heinkel factory near Rostock but a smoke screen conceals the target and the bombs are scattered.
• 8 Stirlings are lost.

• 11 Mosquitos carry out a 'nuisance' raid on Berlin as a diversion for the forces attacking Stettin and Rostock. 18 Wellingtons lay mines off the Brittany ports and there are 3 OTU sorties.
• 1 Mosquito is lost on the Berlin raid.

The Russians bomb Tilsit in East Prussia.

Air Operations, Mediterranean

During a dawn sweep over the sea northwest of Cap Bon, 79th Fighter Group P-40 pilots down 3 Bf-109s and 2 Ju-88s.

Air Operations, New Guinea

• 43rd Heavy Bomb Group B-17s attack the airfields at Borman, Nubia, and Wewak, and shipping off Wewak.
• 90th Heavy Bomb Group B-24s attack Kaimana and Kendari Island.

Bulgarian soldiers posing against the backdrop of the destroyed German military hospital train No684. Six cars of the train in the April 20, 1943 at the high-explosive mine exploded, manufactured by Soviet partisans during the 'rail war'.

Destroyed German Military Hospital Train

Air Operations, Pacific

US aircraft attack the Japanese base on Nauru.

Air Operations, Tunisia

• NASAF B-17s and B-24s attack the Axis landing grounds and airdromes at Creteville, La Marsa, La Sebala, Mabtouha, Protville, and Bizerte/Sid Ahmed.
• 52nd Fighter Group Spitfire pilots down 5 Bf-109s and 2 FW-190s north and west of Tunis between 0915 and 0920 hours.

Aleutian Islands

Rear-Adm Thomas C. Kinkaid, commanding Task Force 16, issues operation orders for the landing on Attu Island.

Diplomatic Relations

Roosevelt meets with Mexican President Manuel Avila Camacho in Monterrey, Mexico, as the 2 'good neighbors' discuss cooperative wartime efforts and make plans for postwar reconstruction.

Japan, Politics

The Japanese Cabinet is reorganized, with Mamora Shigemitsu becoming Foreign Minister replacing Masayuki Tani.

Mediterranean

The US freighter Michigan, in Convoy UGS-7, is torpedoed and sunk by U-565 off the coast of North Africa. The 37 crewmen, 23 Armed Guard sailors and 1 passenger all survive. The French steamship Sidi-Bel-Abbes is also sunk by U-565. The survivors from Michigan help rescue those from Sidi-Bel-Abbes who are Senegalese soldiers. The British escort trawlers Stella Carina and Foxtrot rescue Michigan's survivors who are transferred to the British sloop Felixstowe and taken to Oran.

North Africa

Over the next 3 days Montgomery mounts a series of attacks on the Axis positions near Enfidaville north of Sousse, but these are very strong and the attacks fail with heavy casualties. The Takrouna strongpoint, however, is taken by the British troops.

28 Battalion RAP (Regimental Aid Post) at Takrouna, Tunisia 20 April 1943

US II Corps forces smash through the mountains north of Medjez el Bab, opening the way for the tanks to advance into the Tine River valley.

In the British 1st Army area, as the V and IX Corps are preparing for the assault on Tunis, a German tank-infantry force counterattacks sharply, during the night, in the region between Medjez el Bab and Goubellat.

In the British 8th Army area, the X Corps, continuing the attack on the Enfidaville line, takes Enfidaville and pushes northward on the right but is checked on the left at Djebel Garci by stubborn opposition.

Occupied Poland

The massacre of the Jews in the Warsaw ghetto begins. Under orders from Himmler at least 56,000 will be killed by May 16.

The original German caption reads: 'An assault squad'. SS men on the Nowolipie street of Warsaw Ghetto during the uprising.

SS Troops in Warsaw Ghetto

Pacific

The US submarine Scorpion (SS-278) sinks the Japanese gunboat No. 1 Meiji Maru (1934t) off the east central coast of Honshu.