Battle of Kharkov. German 1st Panzer Army attacks into the base of the Izium salient, aiming to halt the Soviet offensive and encircle their Armies. After a 90 minute artillery barrage, tanks of Kleist's 3rd Panzer Corps attack with air support and crush the Soviet defenses on the edge of the salient, opening a 12 mile wide breach and advancing 10 miles to capture Barvenkovo. Despite this, Soviet forces continue pushing West, deeper into the pocket.
Caribbean. At 0.44 AM 200 miles South of Grand Cayman Island, U-103 uses the deck gun to sink American SS Ruth Lykes carrying 39,136 bags of coffee from Colombia to Houston (6 killed, 26 survivors). Near Grenada, U-155 sinks British tanker MV San Victorio on her maiden voyage at 2.17 AM (52 killed, 1 survivor gunner Anthony Ryan is picked up by US patrol yacht USS Turquoise and landed at Trinidad) and American MV Challenger at 9.52 AM (8 dead and 56 survivors in 2 lifeboats picked up 11 hours later by USS Turquoise).
480 miles East of Long Island, New York, U-135 sinks British lend-lease ship SS Fort Qu´Appelle on her maiden voyage (14 killed, 11 picked up by Canadian minesweeper HMCS Melville). 100 miles South, U-653 sinks British MV Peisander (all 65 hands picked up by US Coast Guard cutter General Greene).
At 5.34 AM in the Gulf of Mexico 75 miles South of the Mississippi River Delta, U-506 sinks US tanker SS Gulfoil (21 killed, 19 survivors on 2 liferafts picked up after 35 hours by US tanker SS Benjamin Brewster and taken to Galveston, Texas).
At 9.04 AM 500 miles East of Barbados, U-156 sinks British SS Barrdale (1 dead, 52 survivors including 1 rescued by the U-boat picked up by Argentinian passenger ship MV Rio Iguazi and landed at Pernambuco, Brazil).
At 6.04 PM in the fishing grounds 85 miles south of Nova Scotia, U-432 sinks tiny unarmed US trawler SS Foam (1 dead, 20 survivors). Nearby at the same time, U-588 sinks Norwegian SS Skottland (1 killed, 23 survivors).
Japanese aircraft carrier Shokaku arrives back in Japan for repairs after the Battle of the Coral Sea. US submarine USS Triton searches but fails to find Shokaku. However, 430 miles Northwest of Okinawa, Japanese submarine I-64 surfaces in front of USS Triton which sinks I-64 from 6,200 yards with the last torpedo (all 81 hands lost).
70 miles South of the Japanese naval base at Truk, US submarine USS Tautog intercepts Japanese submarines returning from the Battle of the Coral Sea. At 6.48 AM, USS Tautog fires at I-22 and I-24, but misses. At 11.07 AM, USS Tautog sinks I-28 (all 88 hands lost).
US submarine USS Skipjack sinks the Japanese troop transport Tazan Maru in the Southern part of the South China Sea between French Indochina, Malaya and Dutch East Indies.
In the evening, 18 RAF bombers unsuccessfully attack German cruiser Prinz Eugen sails South along the Norwegian coast from Trondheim towards Kiel, Germany (3 aircraft shot down). Another 30 RAF aircraft are intercepted by Luftwaffe Me109 fighters and prevented from reaching Prinz Eugen (4 RAF aircraft and 3 Me109s are shot down in the resulting dogfight).