A small electrical fire at the Pittsburgh Zoo's aquarium prompted an evacuation on Tuesday morning. 

The Pittsburgh Zoo & Aquarium said the fire was reported in the aquarium building shortly before 11 a.m. Firefighters "responded promptly" and quickly got the fire under control, the zoo said in a Facebook post. 

All guests and workers were safely evacuated. The animals are being monitored closely. 

The zoo said the fire was confined to the ductwork, and the building has been deemed structurally sound. 

While smoke in the aquarium has been cleared and fans are in place, the zoo says the building will be closed for the remainder of Tuesday. In a later update, the zoo said that while animal residents are stable, the aquarium will stay closed Wednesday so they can assess air quality and clear out the smell of smoke. 

The Pittsburgh Zoo & Aquarium is home to more than 8,000 animals representing over 600 species. Animals like penguins, blacktip reef sharks and sea turtles live in the aquarium.