The robbery happened on Sunday around 1:45 a.m. in the 800-block of State Street in the Loop.
The employee walked out a back door to take out the trash when a man and a woman approached him with a handgun, police said.
When the employee tried to run away, the man grabbed him and put a knife to his throat and entered the business, police said.
Once inside, the woman pointed the gun at another employee and demanded cash from the safe.
Both victims complied and the suspected ran away in unknown direction.
One of the employees was taken to the hospital after falling and hitting his head during the robbery.
Lou Malnati's told ABC7 Chicago that employee safety is their top priority, and they are working with police.
In light of the armed robbery, the restaurant will close at 9 p.m. on Sunday. They will reopen on Monday at 11 a.m., which is their regular time.
No one is in custody. CPD Area Three detectives are investigating.
No other information was released about the suspects.
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