Foreign workers building a sprawling $350 million American Consulate in Milan were paid less than $2 an hour after being promised fair wages, according to Associated Press interviews with five former employees and a review of their employment letters and pay stubs.

Italian prosecutors are investigating Montgomery, Alabama-based Caddell Construction, a major builder of U.S. diplomatic missions.

Two of its managers in Italy were arrested this month on suspicion of labor exploitation, one while boarding a flight to leave the country and another planning to flee, prosecutors said.