The anonymity of the Internet has long made it ideal conduit for illegal activity, but a popular classifieds website has vowed, with Iowa officials' full support, to increase efforts in fighting child pornography and child trafficking on the site.

Craigslist President Jim Buckmaster signed an agreement last week with the attorneys general of 43 states - including Iowa - and Ernie Allen, the president of the National Center for Missing and Exploited Children, to "combat unlawful activity and improve public safety."

"The agreement is designed to strengthen efforts against illegal activity on Craigslist, particularly trafficking of children," said Bill Roach, a spokesman with the Iowa Attorney General's Office.

More than $2.8 billion were spent on online pornography in 2006, and approximately 100,000 sites currently offer illegal child pornography, according to Family Safe Media Organization studies

The National Center for Missing and Exploited Children estimates that 20 percent of online pornography involves children.

And while child pornography and child trafficking via Craigslist haven't been a concern in Iowa, problems have erupted in other states, Roach said.

Iowa City police Sgt. Troy Kelsay said there have been no complaints involving Craigslist in Iowa City. And while the Internet is commonly used for illicit activity, he said, he hasn't seen it associated with one particular site.

In the agreement last week, Craigslist, which boasts more than 50 million users each month, adopted several measures to reduce illicit activity.

Parties who post ads on the "erotic services" page will be required to give a working telephone number and pay a fee with a valid credit card. Craigslist will make this information available to law enforcement if any illegal activity is reported, Roach said.

Craigslist users will also be able to flag any postings that look suspicious, which will automatically remove the item if numerous flaggings occur.

Also part of last week's agreement: Site designers will continue to explore ways to block illegal posts before they're created.

Craigslist is visited by more than 40 million Americans and receives more than 12 million page views each month. And every month, more than 30 million ads and 10 million images are posted on the site, according to craigslist.org.

Though the nature of the Internet makes quantifying child exploitation online difficult, the National Center for Missing and Exploited Children called the problem "wide-spread."

"We think it's very important, and we salute Craigslist for entering into the agreement," Roach said.