By 1:00 PM, April 30th, 1945, following a previous attack upon the Reichstag had failed, the Soviets were able to concentrate 89 artillery pieces to fire upon the Reichstag.
These Soviet artillery pieces included large 152mm--203mm cannon and truck supported screeming Rocket Launchers, known as Stalin Organs.
Following the Artillery barrage, the Reichstag was consumed in a large cloud of smoke.
The Soviets finally blew a 4 foot wide hole in the side of the Reichstag by firing two mortars at the same time, at a close range. When the Soviets entered the Reichstag, the German defenders continued to defend the Reichstag from within, on several floors, with close lethal hand-to-hand combat.
At 10:50 PM, April 30, 1945, the Soviets reached the roof of the Reichstag to mount the Communist Flag, as fighting continued within the Reichstag for another 24 hours. German resistance against the Soviets within the Reichstag was savage well into thelate afternoon of May 1st, 1945.