Four people have been arrested and released to house arrest after being accused of running a scam to obtain work permits for foreign workers and exploiting the blind in the process. The two men and two women were arrested Monday by the National Economic Crimefighting Unit in a raid that marked the end of a months-long undercover investigation which involved wiretapping. The investigation began after police received intelligence from the Industry, Trade and Labor Ministry about a female suspect who falsely registered foreign workers as caretakers for visually impaired people. The investigation revealed a network of suspects who ran a personnel firm which paid blind people from around the country a monthly sum to declare that the workers cared for them. In reality, the workers were directed to cleaning and construction jobs, after obtaining Interior Ministry work permits through the fictitious declarations. Police said the suspects caused "economic damage" since job places were "taken up by foreign workers who were registered as caretakers but who actually worked in other jobs." According to police suspicions, the foreign workers paid the personnel firm thousands of dollars in exchange for their work permit. Detectives have assembled evidence pointing to 20 incidents of fictitious registrations, police said. After being arrested on Monday morning, Ramle Magistrate's Court Judge Ami Kobo released the suspects to house arrest. In a separate incident Tuesday, six Chinese foreign workers mounted a construction crane in Be'er Yaakov, south of Rishon Lezion and refused to come down, in protest over the terms of their employment. Police were called to the site and began negotiations with the workers to end the standoff. After a few hours, the protesters were talked into descending to safety. The workers told police they took the drastic action after becoming upset over conditions that were imposed on them by the personnel firm that was employing them. Officials from the Interior Ministry and the Industry, Trade and Labor Ministry have begun an investigation into the workers' claims of exploitation.