More than one-half of US adults surveyed say they are concerned about identity theft during the holiday season, and two-thirds think that online purchases carry more identity theft risk, according to a survey by the National Association of Insurance Commissioners.

More than 8 million Americans were victims of identity theft in 2005, according to the Federal Trade Commission.

"Identity theft is one of the fastest-growing crimes in the United States, affecting consumers of all ages," said NAIC president Sandy Praeger. Nearly one-third of respondents said they were identity theft victims or knew one. Almost one-half of identity theft victims lost more than $1,000 in the crime.