needs an explanation
SPOILER ALERT: DO NOT READ IF YOU STILL HAVEN'T SEEN THE FILM
I didn't fully understand how at the end the gun dealers brother/friend/associate tracked down Sun-woo at the end even knowing where to enter the building and was shooting everyone that was close without even knowing what his target looked like yet somehow finds Sun-woo and acts like he knows its the guy who killed the gun dealer & crew?
Thanks for clearing this up for me in advance.