McDonald's and Tesco.Fifteen people were treated at the scene and one person was taken to hospital after they suffered a range of symptoms from difficulty breathing to palpitations.
Witnesses reported seeing emergency responders in hazmat suits, Birmingham Live reports, and the fire service remained on the scene until 10:30pm.
One Facebook user warned others in the area to stay clear, saying on Tuesday evening: "Hope no-one is injured and everyone is safe by the Tesco in Gornal."Just been past and there are numerous fire engines, police and ambulances.
Looks like they have taped it off."West Midlands Fire Service said: "We were called at 7.27pm to an incident involving one man entering into Pizza Hut and allegedly entering into McDonald's.
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