Hackers who stole customer information from the company that owns Winners and HomeSense did not access Canadian debit card transactions, the president of the retail chains said Saturday.

That's the conclusion after TJX Cos., the U.S. parent firm of Canadian retailers, conducted its own investigation into the breach it reported on Jan. 17, Winners and Homesense president Michael MacMillan said.

MacMillan expressed his "deepest regrets" over the incident in a full page ad in the Toronto Star.

"Based on our investigation, we can now report that we believe that transactions using debit cards issued by Canadian banks were not involved in the systems breach," he said.

TJX Cos. revealed in January that millions of credit card accounts may have been compromised after hackers stole customer information from its computer systems. The company said the stolen information covers transactions from 2003 into 2006.

The company, based in Framingham, Mass., said at the time that the full extent of the theft and number of customers affected was not known.

MacMillan tried to assure customers in Saturday's ad that the company was taking the problem seriously.

He said it has increased security of its computer systems, hired two computer security firms to investigate the problem, told police about the crime and worked with major credit card companies to protect customers whose credit card information may have been stolen.

"I wish to express my deepest regrets for any difficulties you may have experienced due to this incident. At Winners and HomeSense, our customers have been our top priority for more than 20 years and I can assure you that you will always come first," he said.

According to CP, Canada's privacy commissioner and Alberta's information and privacy commissioner are investigating how the security breach occurred.

TJX, a U.S. discount retailer, discovered the problem in mid-December after hackers got into its computer systems. The systems process and store information about transactions using credit and debit cards, cheques and merchandise returns.

TJX operates 184 Winners and 68 HomeSense stores in Canada.

It also has 826 T.J. Maxx, 751 Marshalls, 271 HomeGoods, 162 A.J. Wright stores and 36 Bob's Stores in the United States. In Europe, the company runs 212 T.K. Maxx stores.

With files from the Canadian Press