Customers were shopping Saturday morning at the Aurora Walmart when gas was smelled and it forced employees to usher everyone outside and shut down the store. Firefighters and first responders arrived to the store off U.S. 50 at about 5 a.m.
One employee was taken to a hospital as a result.
Investigators determined that the smell was linked to malfunctioning heating and air conditioning units on the roof of the store. The store reopened Saturday.