SIOUX FALLS, S.D. (AP) _ A day after the conviction of a Missouri man on federal child pornography charges, U.S. Attorney Karen Schreier said her office is prepared to deal with Internet scams.

Schreier said Tuesday's conviction of Jack Chew, 54, is the first of what she believes will be many prosecutions for crimes committed over the Internet.

Chew, a used car salesman from St. Joseph, Missouri, was convicted of transporting child pornography across state lines. He could be sentenced in March to 15 years in prison and fined $250,000.

Chew had brought his computer to a company in Sioux Falls for repairs when more than 150 pictures of naked children, some engaged in sex acts, were discovered.

He claims he was trying to find out where the pictures came from so he could stop the spread of pornography. And Chew said the pictures did not exist because his computer was broken when he shipped it to South Dakota.

Schreier said her office has five people under indictment for child porn on the Internet.

Internet crime can be easy to prosecute because material clearly crosses state lines, breaking federal law, she said.