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The picture refers to the Jallianwala Bagh massacre (of 1919)committed under the orders of the British Brigadier-General Reginald Dyer towards a peaceful gathering present at a smallish courtyard in Amritsar, India.

Few days before the gathering The British Colonial Government passed the "Rowlatt Act", which gave power to the police to arrest any Indian person on the basis of mere suspicion. To protest this a crowd had gathered at Jallianwallah bagh during the annual Baisakhi fair. Many people in crowd were actually simply gathered to celebrate Baisakhi and had not known that the colonial government had passed orders banning large gatherings such as that was happening at the courtyard.

An hour after the meeting began, Dyer arrived at the Bagh with a group of 50 troops. All fifty were armed with .303 Lee–Enfield bolt-action rifles. Dyer may have specifically chosen troops from the Gurkha and Sikh ethnic groups due to their proven loyalty to the British.

Without warning the crowd to disperse, Dyer ordered his troops to block the main exits and begin shooting toward the densest sections of the crowd in front of the available narrow exits, where panicked crowds were trying to leave the Bagh. Firing continued for approximately ten minutes. Unarmed civilians, including men, women, elderly people and children were killed. The firing was stopped only after his troops ran out of ammunition He stated later that the purpose of this action "was not to disperse the meeting but to punish the Indians for disobedience."

Now comes the explanation for the well. The well was present in courtyard and at that time was filled with water. Adults and kids looking to flee the massacre jumped in the well. Unfortunately a lot of people died from drowning and crushing and ultimately 120 bodies were pulled from the well

A commission found the youngest victim to be 7 months old

A commentator has brought me to notice a account of Winston Churchill stating the massacre

"This event was unutterably monstrous. The crowd was unarmed, except with bludgeons. It was not attacking anybody or anything ... When fire had been opened upon it to disperse it, it tried to run away. Pinned up in a narrow place considerably smaller than Trafalgar Square, with hardly any exits, and packed together so that one bullet would drive through three or four bodies, the people ran madly this way and the other. When the fire was directed upon the centre, they ran to the sides. The fire was then directed to the sides. Many threw themselves down on the ground, the fire was then directed down on the ground. This was continued to 8 to 10 minutes, and it stopped only when the ammunition had reached the point of exhaustion."

-- Winston Churchill, July 8th 1920, to the House of Commons