Baghdad (CNN) -- About 400 members of an exiled Iranian opposition group who are the first to leave a long-term camp in Iraq under a U.N. plan criticized their treatment and the conditions at the new temporary site Saturday. The group left Camp Ashraf at midnight following 12 hours of inspections and checks, Shahin Gobadi of the National Council of Resistance of Iran said in a statement. When they arrived seven hours later at the new site, a former U.S. military base near Baghdad International Airport called Camp Liberty, the group discovered a heavy presence of police. Another inspection was then demanded, prompting the residents to protest what they consider "degrading, humiliating and inhumane treatment" and the obstructive behavior of the Iraqi forces by refusing to leave the transit buses, Gobadi said.
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NEW: "This is the first step towards a better future outside Iraq," a U.N. official says
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About 400 residents of Camp Ashraf leave for a temporary site at a former U.S. base
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The Iranian exiles say they are being inhumanely treated by Iraqi authorities there
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Under the plan, the U.N. intends eventually to resettle the group to third countries
The temporary facility, at what was formerly the U.S.-run @placeholder, will remain open for an unspecified period of time, though a senior U.S. administration official said in December that there were plans to keep it open until all of the camp residents were resettled.