A man is wanted by police after a shopping centre was evacuated when people suffered breathing problems.
Emergency services were called to the Hildreds Centre in Skegness, Lincolnshire on Tuesday "to a report of an unknown substance," police said.
Lincolnshire Police said they were looking for Scott Rowen, 27, in connection with the incident.
A 25-year-old man arrested on suspicion of a public order offence was released on bail.
A number of fire engines and a hazardous materials team attended the scene. Police said no injuries were reported and they had "no further information" on the substance involved.
The centre was reopened following the incident.