Federal agents have begun the process of seizing a Fifth Avenue skyscraper and a Queens mosque from a Muslim nonprofit secretly run by the Iranian government. The Alavi Foundation owns 60 percent of the Piaget building at 650 Fifth Avenue, which was valued at $650 million in 2007. According to a Manhattan US Attorney, the foundation has been secretly controlled by a series of Iranian ambassadors to the U.N. for the past 20 years. The Imam Ali Mosque in Woodside, Queens, is the Feds's other area target. They're also going after properties in California, Maryland, Virginia and Texas. [NYDN]