Police were called to a 99p shop in Wrexham when crowds caused a "stampede" after it began selling its stock half price.
Eager shoppers descended on the outlet in north Wales after the store displayed posters advertising a sale in which all items would be reduced to 50p.
The sale saw people reportedly queuing onto the street in order to grab an even bigger bargain at the 99p shop.
Within hours, most of the shelves were completely stripped of the goods due to the demand, with witnesses saying people acted like "vultures" once inside.
Police were called to the shop after shoppers became angry when the management brought the prices back up to 99p while they were still in the queue. Customers reportedly refused to move from the shop.
One shopper, Sharon Roberts, told News North Wales: "I was in there for nearly two hours queuing to get to the till. Then the manager took the posters down from the window.
"People were absolutely furious and that's why the police were called. Tempers were flaring and people were shouting. The shop finally said people could have items on a buy-one-get-one-free."
Another, Phil Smith, added: "They dropped all the prices to 50p until 28 January, and there were queues of about 40 to 50 people all day. Then the manager came around saying everything is back up to 99p.
"I am so angry, you can't do that, not when people are in the queue to pay. The police had to come because the people were not having it and not leaving."
Four police officers were called to control the crowds inside, with one staying outside to direct people away from the busy store.
North Wales police said: "We were told there was a sale on and that the shop was very busy. The shop had to be closed down temporarily. There were no arrests made."