The number of websites running online identity theft scams - phishing - grew by 33 percent in November, after dropping off in September and early October, according to data compiled by the Anti-Phishing Working Group (APWG).

The group received reports of 1,518 active phishing sites last month, up from 1,142 in October. Reports of such sites have grown by an average rate of 28 percent per month since July, as scam artists broadened their efforts to lure customers of companies that do business online, according to Peter Cassidy, secretary general of the APWG. The APWG is an industry group of representatives from law enforcement and private sector companies, including leading ISPs, banks and technology vendors.

Phishing scams use spam to direct Internet users to websites that are controlled by thieves, but designed to look like legitimate e-commerce sites. Users are asked to provide sensitive information such as a password, bank account information or a credit card number, often under the guise of updating an account.

Customers of 51 online brands were targeted by phishing scams in November, compared with 44 brands in October, Cassidy said. However, just six companies drew more than 80 percent of all phishing scams, he said.

The APWG no longer identifies the organisations that were the most popular targets of phishing scams, citing resistance from the group's industry members, he said. However, eBay and Citibank were phishers' top targets in past months, according to previous APWG reports.

The creation of phishing sites in October and November resumed the torrid pace it reached in mid-August, after dropping off for much of September.

Phishing attacks have emerged as a potent threat in 2004. More than 18 million e-mails linked to the attacks have been stopped this year by e-mail security provider MessageLabs. Industry groups, including the APWG, responded by calling attention to new attacks and working to shut down sites used in the scams to harvest personal information from unsuspecting Internet users.

Recently, leading companies and law enforcement agencies unveiled a new anti-phishing initiative. Digital PhishNet brings together companies such as Microsoft, AOL and VeriSign with the FBI, US Secret Service and US Postal Inspection Service. The US remains the most frequent host of fraudulent Web pages used in the attacks, Cassidy said.

While phishing attacks may spike during the pre-Xmas months of November and December, the increasing number of anti-phishing tools and initiatives will hopefully bring the number of attacks down in 2005, according to Neil Creighton, chief executive officer of GeoTrust, a provider of online digital certificates.

Like other companies, including Earthlink and eBay, GeoTrust distributes a free Web browser plugin that warns users when they visit phishing sites. Such utilities, coupled with the efforts of groups like the APWG and Digital PhishNet, will make life harder for online scam artists, and prompt consumers and merchants to become more aware about online identity verification, Creighton said.