April 13th, 1942 (MONDAY)
UNITED KINGDOM: Rear Admiral Lord Mountbatten is appointed Chief of Combined Operations and functions as a member of the British Chiefs of Staff Committee. This appointment announced today was effective March 18.
FINLAND: Colonel Aarne Snellman, CO of the Finnish 17th Division is seriously injured at his divisions command post at Vaaseni (Vazhiny by River Svir in Olonets Isthmus) when it is attacked by Soviet night bombers.
LITHUANIA: Vilna: Feldwebel Anton Schmid, an Austria NCO in the German Army assigned to duties in occupied Lithuania is executed. He is guilty of providing food and medicines to Jews assigned to his workshop, and also of helping Jews escape from the ghetto and warning them of imminent SD 'Aktionen'. (Russ Folsom)
GERMANY: The German radio announces the finding of mass graves in Katyn, Poland, filled with the bodies of thousands of Polish officers.
BURMA: Allied forces retreat to Magwe, leaving the oilfields of central Burma exposed to the Japanese.
COMMONWEALTH OF THE PHILIPPINES: The last boat of US Navy Motor Torpedo Boat Squadron 3 is transferred to the US Army.
Australia-based B-25 Mitchells bomb targets in the Philippines for the second consecutive day. Staging through Del Monte Airfield on Mindanao, the B-25s take off just after midnight on 12/13 April and bomb shipping at Cebu on Cebu Island and installations at Davao on Mindinao. Later in the day the B-25s again attack Davao, bombing the dock area.
PACIFIC OCEAN: Submarine USS Grayling (SS-209) torpedoes and sinks a Japanese merchant cargo ship off the southwest tip of Shikoku, Japan.
SOUTH PACIFIC: Vice Admiral Robert L Ghormley, USN, is assigned as Commander-in-Chief South Pacific (COMSOPAC). He is to command all Allied base and local defence forces (land, sea, and air) in the South Pacific Islands, with the exception of New Zealand land defences.
BURMA: Allied forces retreat to Magwe, leaving the oilfields of central Burma exposed to the Japanese.
U.S.A.: The Federal Communications Commission (FCC) mandates that the minimum program time required of TV stations is cut from 15 hours to four hours a week for the duration of the war.