Western Front
Royal Flying Corps destroys 2 German balloons (3 British aircraft lost) and damage 3 more. Arras bombardment renewed. 2 new Sopwith Triplanes of Royal Navy Air Service No 1 Squadron disperse 14 German DFW CVs and shoot 3 down at 16,000ft before they can reconnoiter the BEF lines.
Shoot down of an observation balloon. The observer could jump off by parachute in the picture on the left: https://i0.wp.com/ww2-weapons.com/w...allon.jpg?ssl=1
Somme: British 40th Division (Fourth Army) captures three local objectives (incl on April 24 and 25).
Aisne: Mangin protests at offensive continuing, despite announcements of it being discontinued the day before; ammo supply critical. Tenth Army (Duchene) committed between Hurtebise and Berry-au-Bac.
British officers drinking tea in St. Quentin: © IWM (Q 2085) https://twitter.com/CenturyAgoToday...5881728/photo/1
65,000 German shells have been fired on the city of Rheims since April 1st. French official calls it “abominable vandalism.”
In the ongoing offensives on the Western Front, Allied troops claim to have captured 33,000 German prisoners and 330 artillery guns.
Troops of the Indian Army in the ruins of Caulaincourt, France: © IWM (Q 2080) https://twitter.com/CenturyAgoToday...5145345/photo/1
ritish cavalry passing through Caulaincourt in pursuit of the Germans: © IWM (Q 2074) https://twitter.com/CenturyAgoToday...9876352/photo/1

Naval and Overseas Operations
German submarine SM UC-30, credited with sinking 5 ships, hits a mine and sinks with all hands.

Asiatic and Egyptian Theaters
Mesopotamia: Battle of Istabulat (until April 22). General Cobbe with 7th Division (2,228 casualties) and 76 guns twice attacks Shefhet’s 7,000 Turks (c.2,200 casualties including 700 PoWs) with 31 guns astride railway, taking position and 1 gun. Lieutenant Graham (MG Corps) wins 23rd and last Victoria Cross of the campaign.
Palestine: Chetwode replaces Dobell as GOC (General in command) Eastern Force, Chauvel takes over Desert column.
Cossacks repulse Kurds on Diala (north-west of Kasr-i-Shirin).

Political, etc
Russia: On 20–21 April 1917 massive demonstrations of workers and soldiers erupted against the continuation of war. Demonstrations demanded resignation of Minister of Foreign Affairs Pavel Milyukov. They were soon met by the counter-demonstrations organised in his support. General Lavr Kornilov, commander of the Petrograd military district, wished to suppress the disorders, but premier Georgy Lvov refused to resort to violence. Decree of Russian War Minister Alexandr Guchkov re: Army.
United Kingdom: British government states all doctors must report for military service due to the need to establish hospitals near the frontlines.
“American flag day” in London to celebrate the U.S. entrance into WWI: https://twitter.com/CenturyAgoToday...4768385/photo/1
Spain: In the first meeting of the new Spanish Cabinet, it announces the country will continue to maintain strict neutrality in the war.

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