A federal prosecutor frustrated with an increase in the number of sexual predators (search) who seek out young children saved up 16 cases in his Kansas district and put them before the same grand jury, hoping to illustrate the scope of the problem.

U.S. Attorney Eric Melgren (search) draws no distinction between those who take lewd photographs of children and those who collect such images.

"I think it's a serious threat to our children out there that people who are looking at these pictures may mimic the action or themselves create these pictures," Melgren said. "Sadly, I suspect that most of these go undetected."

With the 16 indictments announced Thursday — 15 against Kansans for child pornography and one against an Arizona resident for traveling across state lines to have sex with a minor — Melgren's office has issued 30 indictments this year for those types of crimes.

That's a significant increase over the indictments his office issued for child pornography in previous years, including 22 each in 2002 and 2003.

Two of the 15 Kansas residents who were indicted Thursday already were on the state's sex offender list, according to a spokesman for Kansas Attorney General Phill Kline (search).

Nationally, the number of child porn/child exploitation cases handled by the FBI grew from 113 in 1996 to 2,370 in 2002.