Credit card and payments company MasterCard says that it is partnering with NameProtect, an online brand protection service, to combat online identity theft and a black market in stolen credit card numbers.

The two companies will combine their efforts against phishing scams and online identity thieves, taking "a more aggressive approach" to cyberscams that affect consumers and companies.

MasterCard will have access to data from NameProtect's technology, which can search and filter large volumes of internet content to find online scams.

The companies will also work with law enforcement agencies to shut down internet sites and tools used by identity thieves, the companies say in a joint statement.

Phishing scams are a form of online crime in which unsolicited commercial ("spam") email is used to direct internet users to websites controlled by the thieves, but designed to look like legitimate e-commerce sites. Users are asked to provide sensitive information such as a user name and password, social security number, bank account or credit card number, often under the guise of updating account information.

Phishing scams have surged in recent months. The number of scams reported increased by almost 200 percent, to 1100 in April, a 178 percent increase from March, according to figures from the anti-phishing working group, a computer security industry group.

Customers of online retailers such as EBay and CitiBank are frequently the attacks' targets.

As part of the partnership, NameProtect will use its internet detection technology and systems to monitor a variety of online information sources to identify new fraud campaigns.

The company's technology can filter information from internet domains and web pages, as well as online discussions and spam email to identify online trading rings, phishing attacks and other forms of online fraud, according to the statement.

US-based NameProtect will report information on new threats to MasterCard, which will issue alerts to its 25,000 member network of financial institutions using a service called MC Alerts. Those organisations can then alert their customers, the companies say.