CALGARY -- Police say tear gas was set off by a group of assailants that ended up robbing a jewelry store inside a northeast Calgary mall Saturday.

Calgary police were called to Sunridge Mall on 36 Street N.E. for reports of a commercial robbery at about 1:30 p.m.

Officials say the business, Paris Jewellers, had been targeted by a group of unknown suspects.

Additional calls to the fire department and EMS were made after it appeared the thieves released tear gas inside the business.

Fire crews initially believed the incident was some sort of fire because of the thick haze, but found no flames and quickly realized it was caused by some sort of substance. As a result, the entire mall was evacuated and closed off.

The CFD, along with EMS, assessed about 20 patients at the scene and one adult male was taken to hospital in non-life threatening condition.

No one else appears to have been hurt in the incident at the store.

Officials say it could be hours before the mall is cleared of the substance and decontaminated because it managed to get into the facility's ventilation system. It's unlikely it will reopen before the end of day Saturday.

Calgary police say they are looking for two suspects who stole an undetermined amount of merchandise from the store. One of the suspects was wearing a helmet while the other had a disposable face mask covering their face. That suspect was also armed with a shotgun, but it was not fired during the incident.

The shopping mall remains blocked off.

Correction:

This copy has been updated to omit the previous reference of the suspects in this robbery being Black. That was based on the description provided to CTV News by CPS at the time of publication.