Four men accused of organizing a prostitution ring that involved at least two Hawai'i girls were among 19 people arrested nationwide this week in an investigation of sex trafficking.

U.S. Attorney General Alberto Gonzales announced yesterday that 31 people have been charged and 19 arrested in the past two days as part of the government's "Innocence Lost" investigation.

Federal, state and local authorities took part in the investigation, which targeted child prostitution and rings that lured children into the sex trade.

Over the past two days, indictments and complaints were unsealed in Hawai'i, Pennsylvania, New Jersey and Michigan, charging 31 people with crimes related to child prostitution. As part of the investigation, 30 children have been rescued from the trade, Gonzales said, including two in Hawai'i.

Charles Goodwin, FBI special agent in charge in Honolulu, said four Michigan men have been charged with transporting women and girls between Honolulu and Detroit to work as prostitutes. The ring operated from November 2003 to July 2005, according to one of the indictments.

Goodwin said the two Hawai'i girls were between 14 and 16 years old when they were recruited into the trade. He said they have since returned to their families and are cooperating in the investigation.

"With children, young girls, runaways, they fall victim to these situations and they're easily exploited," Goodwin said. "They're young and they're impressionable and it's easy for people like this to prey on them and exploit them."

U.S. Attorney Ed Kubo yesterday applauded the investigation.

"Our community has no tolerance for those who come to Hawai'i and prey on our children for the purpose of fueling their prostitution operations," Kubo said. "We will aggressively prosecute anyone who uses our islands to recruit or profit from prostitution activities, especially involving our youth."

The Hawai'i ring also involved women, some of whom were forced to work as prostitutes, Goodwin said. He said the prostitution operation was advertised on the Internet as an escort service.

Goodwin said the four men accused of being involved in the Hawai'i-Detroit ring are: