By Mugo Odigwe

CHICAGO (CBS)– Six people were injured in a high-rise fire in The Loop early Tuesday morning.

The building, at 400 East Randolph, located near Maggie Daley Park, caught fire sometime after 12:30 a.m. The fire was located in a single unit on the 32nd floor and it appears to be electrical in nature, but the cause is unknown.

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While responding to the fire, five firefighters became temporarily stuck in an elevator. They were not injured.

A 60-year-old woman and a 77-year-old man, who live on the 32nd floor of the building, are in the hospital in serious condition. A third person was also taken to the hospital, but his condition was not serious.

Most of the people injured are suffering from smoke inhalation.

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A resident’s pet, a cat, died in the fire. The fire was struck out around 1:30 a.m. and most residents have been able to return to the building.