New York, NY —

The federal government has taken steps to seize a New York City skyscraper, a mosque in Queens, and mosques in three other states, claiming the nonprofit Muslim group that owns them, is secretly controlled by Iran's government.

Prosecutors are seeking the forfeiture of more than $500-million in assets of the Alavi Foundation and an alleged front company, Assa Corporation. Those assets included the Piaget Building at 650 Fifth Avenue, and a mosque and school in Woodside, Queens.

Prosecutors say the foundation illegally funneled millions of dollars to Iran's state-owned bank, which, in turn, has been accused of supporting Iran's nuclear program.

The Council on American-Islamic Relations has expressed concern that the seizure of mosques could have a chilling effect on religious freedom.

If successful, the counterterrorism seizure could be one of the biggest in US history.