A Sainsbury's superstore in Ipswich was closed on Thursday evening while emergency services attended a serious incident.
Police and paramedics, including the air ambulance, were called to the supermarket in Hadleigh Road at about 2.50pm on Thursday.
A spokeswoman for Sainsbury's said: "Our Hadleigh Road Superstore was temporarily closed to support the emergency services.
"We will reopen as soon as possible and are sorry for any inconvenience this may cause.”
A Suffolk police spokeswoman confirmed that officers were at the scene and the car park was also closed off.
The East of England Ambulance Service has been approached for a comment.
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