Identity theft was the top complaint filed by U.S. residents to the Federal Trade Commission in 2011, with Internet-related fraud also a top concern, the agency said Tuesday.Fifteen percent of the 1.8 million complaints the FTC received through its online Consumer Sentinel Network involved ID theft, the agency said. Fifty-five percent of the complaints involved some type of other fraud, and of the people who reported where that fraud originated, 43 percent said email and 13 percent said a website. Twenty-nine percent of the fraud complaints started with a phone call, the FTC said.Under identity theft, government benefits or documents fraud made up 27 percent of the complaints, credit card fraud made up 14 percent and telephone or utilities fraud made up 13 percent, the FTC said. Identity theft made up 17 percent of the complaints to the FTC in 2010 and 20 percent of the complaints in 2009. The FTC received 1.5 million complaints through the online database in 2010, and 1.4 million in 2009. Since 2001, the number of complaints has risen every year except for one.The online database is an "incredibly powerful tool for law enforcers who are working to protect consumers and go after the bad guys," David Vladeck, director of the FTC's Bureau of Consumer Protection, said in a statement. "It's used by agencies across the country and around the world to enhance their enforcement efforts."Other federal and state law enforcement agencies contribute complaints to the Consumer Sentinel Network, including the U. S. Postal Inspection Service, the U.S. Department of Justice's Internet Crime Complaint Center and the offices of eight state attorneys general. Other organizations that contribute complaints include all U.S. and Canadian members of the Better Business Bureau, Western Union and Moneygram. Debt collection complaints were 10 percent of the total complaints in 2011, the agency said. Prizes, sweepstakes and lottery complaints made up 6 percent. Complaints about Internet services were the sixth largest category, at about 5 percent, and complaints about telephone and mobile services ranked ninth, with 4 percent.The median loss for all the fraud complaints -- not including ID theft -- was US$537, the FTC said.Florida was the state with the highest per capita rate of reported ID theft complaints, followed by Georgia and California. Colorado was the state with the highest per capita rate of reported fraud and other complaints, followed by Delaware and Maryland.Grant Gross covers technology and telecom policy in the U.S. government for The IDG News Service. Follow Grant on Twitter at GrantGross. Grant's e-mail address is firstname.lastname@example.org.