Selangor state police said the suspect fired four shots at the janitor after entering the shopping mall in Setia Alam, located about 34km from capital Kuala Lumpur.
Police said the suspect shattered a glass stairwell window along with a sliding door before escaping into the car park.
An employee at the mall sustained injuries after a man opened fire at about 10.50pm (local time) on Saturday, police said.
He said the suspect forced the driver to get him out of the mall and then instructed the driver "to drop him off near the Pandamaran exit of the Kesas Expressway".
The police recovered more than 10 bullet casings from various areas of the mall and the car park as video from the shooting showed terrified shoppers scrambling for cover.
