Aviv Raff

The hackers who raided the credit card payment system of Neiman Marcus Group set off alerts on the company’s security systems about 60,000 times as they slunk through the network, according to an internal company investigation. The hackers moved unnoticed in the company’s computers for more than eight months, sometimes tripping hundreds of alerts daily because their card-stealing software was deleted automatically each day from the Dallas-based retailer's payment registers and had to be constantly reloaded. Card data were taken from July through October.