The Canada unit of Bell revealed that the user names and passwords belonging to 22, 421 small business customers were posted illegally online this weekend, Bloomberg reported. BCE Inc also said that five valid credit card numbers were also included in the posting.

The company said that a hacker was able to get access to the systems of an Ottawa third-party technology supplier which Bell uses and then leaked the information on the Internet. Montreal-based Bell added that Quebec and Ontario customers were affected, the report said.

In an answer to questions sent by Bloomberg, Bell Spokesman Jean Charles Robillard said through email, "The supplier provided an ordering application for some small-business services." He added that it's their issue since it impacts their customers. Robillard; however, did not reveal the name of the provider but went as far to say that it was not an Internet service provider.The statement about the breach said that Bell had informed its clients, rendered the passwords inoperative and had also contacted the affected credit card firms, Bloomberg reported.

Bell added that it is collaborating with suppliers, law enforcement as well as government security officials to conduct an investigation on the matter. According to the company, the breach did not compromise its network and systems. Residential, mobility or enterprise business customers of the company were not also affected by the attack. Bell is the second biggest wireless carrier in Canada, the report said.

According to a report in the Canadian Press, a hacking group that goes by the name of Nullcrew said they were behind the attack. The claim was made through a post in Twitter which also placed a link to the stolen information.

Bloomberg data showed that BCE Inc provides local, long distance and wireless phone services. Its services also include high-speed and wireless Internet access, IP-broadband services and direct-to-home satellite and VDSL television services, among others.