Birmingham’s Bullring shopping centre was closed down for part of Thursday after several people fell ill following a suspected chemical leak.
Before the Bullring opened in the morning, security staff had been taken into hospital after breathing in fumes from a chemical incident.
Although the centre re-opened it had to be closed again after the smell returned with around 20 people complaining of nausea. 250 Bullring staff have been screened by a doctor.
A spokeswoman for the Bullring said that the chemical fumes had come from a security room in the basement of the centre.
Five people were taken to hospital but have now been released.