Israel Police working as part of an international operation arrested a number of Israelis believed to be involved in Internet pedophile circuits, and who are suspected of downloading disturbing images of very young children. The crackdown came on Monday morning following an undercover investigation that crossed the world. Detectives of the Computer Crimes Desk of the National Fraud Squad raided four houses in Israel. Following the searches, the investigators detained six suspects, including a father and son, as well as both members of a couple. The operation was carried out under the auspices of an international operation that was coordinated with overseas law enforcement organizations. The suspects are believed to have held computerized material with what police described as "pedophilic content." Police said the suspects allegedly downloaded the offensive content from the Internet. After conducting searches at the houses of the suspects, police also confiscated computers, hardware and additional items that they believe may have been related to the alleged offenses. The investigation began overseas in 2006, and in the course of the investigation evidence was gathered against hundreds of suspects worldwide. The six Israeli suspects were among those hundreds, and police believe they had visited a number of Web sites that contained pedophilic material, including pictures and files that included "strongly pedophilic content." Some of the files, police said, featured "extremely young children" who appeared to be under the age of 10. According to data presented by UNESCO's Innocence in Danger project, approximately 50,000 pedophiles worldwide may be prowling the Internet at any given moment. In February, a similar international operation in the UK resulted in a series of arrests after UK law enforcement officials teamed up with their Australian, Canadian and American counterparts. The international ring that was revealed by that investigation seemed to investigators to include approximately 300 members.