Masked robbers told staff they would kill them if they tried to stop them stealing camera equipment from shop shelves.
Three robbers burst into a camera shop and threatened staff before making off with more than £8,000 worth of equipment.
The men then dashed from Jessops in Swan Walk in Horsham towards Horsham Park.
Sussex Police are now appealing for witnesses to the terrifying raid which took place yesterday at 5pm.
One of the attackers is described as black and wearing a black hooded top, white trainers and dark trousers, a second man was dark skinned, possibly Asian and was also wearing a dark hooded top, dark trousers and white trainers while a third man was white and wearing a white hooded top, jeans and white trainers.
Sergeant Ben Websdale said: "The men ran through the town centre towards Horsham Park at a time when lots of people would have been on their way home so there could be plenty of people who saw them escaping.
"We need to speak to anyone who saw the men or who recognises their descriptions.
"I would also urge anyone who is offered the chance to buy an expensive camera at a bargain price to get in touch with us.
“The thieves may try to sell them off cheaply but if we seize one of the cameras from you, you will not get it or your money back."
Anyone with information should call 101 quoting serial 1175 of 25/6, email email@example.com or call the independent charity Crimestoppers anonymously on 0800 555111.
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