Upscale Honolulu stores have been hit hard losing more than a quarter of a million dollars from high-tech thieves, and local store managers are now on alert.

"It makes you uncomfortable, it makes you be more aware, and be more cautious about people coming into your establishment that are coming in to use credit cards," said James Sosa, manager at The Island Slipper Store.

Police arrested five people for stealing credit card numbers to purchase more than $300,000 of high end merchandise at Waikiki and Ala Moana shops. Two days ago, a couple from New York was arrested for using these counterfeit credit cards stealing more than $10,000 worth of goods.  Police said they were able to catch the last suspected criminals faster than the first five.

"We are getting better at it -- and it actually allowed us to track these people while they were here rather than as you saw with the previous indictment. They fled and we had to put the case together after the fact," said Lt. John McCarthy with the Honolulu Police Department.

Police believe the first group of suspects and the second couple arrested possibly know each other. These types of organized crimes are an expensive problem for banks.

"Credit card fraud in itself is billions of dollars and credit card fraud has been used to finance very criminal units like the Russian mafia," said Edward Pei with Hawaii Bankers Association.

Local stores won't be taking any chances anytime soon.

"When you have mainland customers or international customers we take those extra steps to check passports or double check the signatures everything," said Sosa.

HPD said it's an ongoing process to fight credit card fraud. And they are trying to work with bankers, credit card companies and local merchants to prevent future crimes.