According to police, a security guard from the armored truck was emptying an ATM machine outside the BMO Harris Bank in the 4900 block of West North Avenue around 8:30 a.m. when a dark-colored SUV pulled up next to the machine. Police said the passenger got out and approached the security guard with a handgun and demanded money. The security guard fired shots at the person and struck him in the torso, according to police.