Target says data breach affects 70 million customers

NEW YORK/BOSTON:U.S. retailer Target Corp  said on Friday at least 70 million customers were affected by a cyber-attack over the holiday shopping season, nearly double its original estimate, and warned the stolen data was more detailed than first thought.

Target's announcement raised fears among security analysts that the No. 3 U.S. retailer has not yet fully grasped the scope of the data breach, which is considered the second biggest credit card attack in retail history.