Xu Shuo didn't know if it was because he had been bombed previously, but when it came time to retaliate against the enemy, the Capital Commandant didn't hesitate to throw several grenades in.
However, the grenades in their world were crudely made. Although they exploded with earth-shattering force, they also released a lot of black ash and smoke into the air, causing some degree of environmental pollution.
There was no greenery in this civilian area, and the whole of District 13 could be called a city of steel.
After helping to throw the bombs, Xu Shuo stood aside, watching the rolling smoke and sparks inside, while the troops rigorously defended the area outside the smog, encircling it layer by layer.
Perhaps the military patrol alone might not have discovered this stronghold so quickly, but... don't forget there was a spy from the Radiant Corps amongst them.
If one's temporary stronghold was dragged into the battle, it was certain to attract extra attention.