Classified ad and auction sites: Criminals post ads for goods that don't exist and steal consumers' credit card numbers. Fake checks: Consumers given phony checks in exchange for goods and told to wire money back to the buyer. Prizes/sweepstakes/free money: Requests for payment to claim prizes that don't exist. Gift cards: Fake gift cards sent to people who buy cards through online auction or classified sites. Phishing: E-mails that appear to be from a well-known source ask people to enter personal information. False charities: Organizations that collect money but don't use it for philanthropic purposes. Employment: Fake job offered in exchange for an up-front fee. Nigerian money offers: Promises of money if the person pays to transfer funds to a scammer's bank account
Popular types of scams
Internet merchandise: Goods are either misrepresented or not delivered.
Sources: National Consumers League, FBI
Tips to avoid being a victim
» Don't shop online on an unencrypted or open wireless network.
» Make sure your computer's firewall, anti-spyware and anti-virus software are updated before shopping online.
» Use only reputable sites.
» Pay by credit card so you can dispute the charges if necessary.
» Don't be tempted by free-money offers.
» Look for secure sites that display "https" in the address bar.
» Be cautious of e-mails that ask for information about your financial accounts.
» Do not respond to unsolicited e-mails.
» Contact businesses to make sure e-mails are genuine.
» Place a fraud alert on your credit accounts so you can monitor potential identity theft.
» When shopping, keep your credit cards out of view of nearby shoppers.
Sources: National Consumers League, FBI, Institute for Cyber Security
By the numbers
Number of fraud, identity theft and related consumer complaints
Source: Federal Trade Commission
Number of online fraud reports
D.C.791 708 144
Source: Internet Crime Complaint Center
It's the season for people to pull out their checkbooks and credit cards to buy holiday presents, book travel and donate to charities.

But Washington area consumers do, a growing number of them are getting ripped off. Reports of consumer fraud -- particularly online scams -- have spiked in recent years. And the holidays are prime time for fraud and identity theft, because customers are constantly handing over their credit card numbers and people are more likely to fall for scams.

"The holidays are expensive, and people may not have money for travel, for gifts," said Elaine Lidholm, communications director for the Virginia Department of Agriculture and Consumer Services. "People are willing to toss up their disbelief and common sense."

So they fall prey to scams that include fake online auctions, sweepstakes awards that never arrive and charities that don't exist.

Reports of fraud, identity theft and related consumer complaints jumped 225 percent in Virginia between 2004 and 2009, according to Federal Trade Commission data. And those complaints rose 132 percent in Maryland and 92 percent in the District during that time period.

The still-faltering economy is behind some of that increase, Lidholm said.

"For people who have been out of work, as time goes on, they become more gullible," she said. "They want it to be true so badly."

It's especially easy for that to happen during the holiday season, when people are looking for extra cash, said John Breyault, director of the fraud center at the National Consumers League.

And as more people are shopping online -- the market research firm Coremetrics reported that online sales on "Cyber Monday," the Monday after Thanksgiving, rose 14 percent last year -- the Internet is increasingly a source for holiday scammers.

In the past five years, instances of Internet-related fraud and identity theft increased 449 percent in D.C., 456 percent in Maryland and 388 percent in Virginia, according to the Internet Crime Complaint Center, an arm of the FBI that tracks all types of online fraud.

"Counterfeiters and pirates with basic Web design skills can set up online storefronts that look as authentic as those operated by legitimate enterprises," Maryland Attorney General Douglas Gansler said in a statement. "These web sites are highly deceptive to consumers."

The poor economy is also spurring an uptick in fraudulent charitable organizations, said Daniel Borochoff, president of the American Institute of Philanthropy.

"People see it as a way to make some money," he said.

Organizers of fake charities find many victims around the holidays.

"They exploit consumers who are in the mood to give," Breyault said.

Stores, too, can fall victim to fraud. The National Retail Federation projects that return fraud -- when a person steals an item, then returns it for cash or store credit -- will cost stores $3.68 billion this year, up from $2.74 billion last year. Holiday sales are expected to be somewhat stronger this year, leading to busier stores and more returns, said Joseph LaRocca, the organization's senior asset protection adviser.

And fraud isn't the only danger holiday shoppers need to watch for.

Police are also urging shoppers to stay alert to avoid being a robbery victim and for drivers and pedestrians to be careful in parking lots.

At a Frederick Walmart last week, two shoplifters pulled a knife on a store employee while trying to steal video games.

Officers around the region are stepping up patrols near shopping centers throughout the holiday season. Parking lots are a major site of traffic crashes, especially during the holidays, police say.

Even though scams increase around the holidays, people should be careful at all times, authorities said.

In Loudoun County, which typically gets about three fraud reports a day, more than 40 instances of credit card fraud have occurred in the past week, said Kraig Troxell, spokesman for the Loudoun County Sheriff's Office.

"At any time of the year, you need to keep an eye on your credit card statements and make sure there aren't purchases you didn't make," he said.