A man has been arrested 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.
A number of fire engines and a hazardous materials team attended the scene. Police said no injuries were reported.
A 25-year-old man has been arrested on suspicion of a public order offence.
Lincolnshire Police said the man had been released on bail and officers were still investigating the incident.
Charles Spooner from the shopping centre said the mall's security team "acted swiftly to secure the centre".
"The safety and security of everyone in our centre is always our first priority and are supporting the police with their investigation," he said.
The centre was reopened following the incident.