Shoppers at Westfield Marion say an emergency announcement was made over the PA system just before 4pm (AEST).

Armed officers were seen running into the centre about 10 kilometres south-west of Adelaide’s city centre.

It is understood no one has been injured, but ambulance crews have been called.

Shoppers have described shutters coming down on shops, with people hiding inside.

“My partner and I were in David Jones near the jewellery section and we heard someone over Westfield (speakers) say ‘this in an emergency’,” one shopper told 9News Adelaide.

“Then we heard it again and we’ve never heard that type of thing.

“Next minute the David Jones security doors went down.”

The shopper said she saw a security guard run up the escalators.

A photo posted on X by Nico Nacuse showed a Westfield shopping centre screen with the message “Armed offender. Escape, hide, tell”.

Nacuse said “they are evacuating everyone”.

“At this point in time, police advise the public to stay away from the area,” a police statement said.

“A further update will be provided when known.”

The shopping centre is one of the largest in South Australia and has more than 340 stores.