A car has smashed into the window of the TK Maxx store at Aylesbury's Broadfields Retail Park.
The scene is currently sealed off while emergency services work at the scene.
One eyewitness described a 'huge boom' as they were shopping in Dunelm and other shoppers racing out of the store.
One car is believed to be involved, and the occupant is being treated at the scene.
Firefighters at the scene said that it was being treated as an 'accident and not an incident'.
Another eyewitness claimed to have seen an elderly couple in the vehicle, and fire crews said no one was injured.