Sagot :
The 1905 massacre of protestors outside the czar's palace in St. Petersburg, Russia, is known as B L O O D Y Sunday.
Answer:
It is known as Bloody sunday.
Explanation:
The name of Bloody sunday is given to the events of sunday 22 january 1905 in St. Petersburg. Russia when unarmed demonstrators led by father Gregory Gapon were fired upon by soldiers of the imperial guard as they marched towards the winter palace to present a petition to Tsar Nicholas II of Russia.