One of the world's most popular file-sharing sites was shuttered Thursday, and its founder and several company officials were accused of facilitating millions of illegal downloads of films, music and other content.

An indictment accused Megaupload.com of costing copyright holders at least $500 million in lost revenue. The indictment was unsealed one day after websites including Wikipedia and Craigslist shut down in protest of two congressional proposals intended to make it easier for authorities to go after websites with pirated material, especially those with headquarters and servers overseas.

Megaupload is based in Hong Kong, but some of the alleged pirated content was hosted on leased servers in Ashburn, Virginia, which gave federal authorities jurisdiction, the indictment said.

The Justice Department said in a statement said that Kim Dotcom, 37, and three other employees were arrested Thursday in New Zealand at the request of U.S. officials. Three other defendants are at large.

Before the site was taken down, it posted a statement saying allegations that it facilitated massive breaches of copyright laws were "grotesquely overblown."