US authorities have shut down dozens of websites offering counterfeit goods and pirated music, five months after a crackdown on sites offering movie downloads.

A spokeswoman for the Immigration and Customs Enforcement agency, part of the Department of Homeland Security, told The New York Times the court-ordered seizure of domain names was part of an "ongoing investigation."

She declined to provide further details, but Torrent Freak, a website about the popular BitTorrent file-sharing protocol, published a list of more than 70 sites it said had been targeted.

A visitor to the sites is met with a message reading: "This site has been seized by ICE - Homeland Security Investigations, pursuant to a seizure warrant issued by a United States District Court."

It informs visitors that copyright infringement is a federal crime carrying a penalty of five years in prison and a 250,000-dollar fine while trafficking in counterfeit goods carries a 10-year sentence and a fine of two million dollars.

The sites targeted included burberryoutletshop.com, cheapscarfshop.com, dvdcollectionsale.com, handbagcom.com, mydreamwatches.com, rapgodfathers.com, sunglasses-mall.com, torrent-finder.com and usaoutlets.net.

The move comes almost exactly five months after US authorities launched a crackdown on websites offering pirated copies of movies.

The domain names of nine websites offering first-run movies were seized in late June along with bank, Paypal and advertising accounts as part of what US officials dubbed "Operation in Our Sites."

US authorities said at the time that "Operation In Our Sites" would target not only pirated movies but other items distributed over the Internet such as music, counterfeit pharmaceuticals, software, electronics and games.

The Senate Judiciary Committee approved a bill last week that would give US law enforcement even more tools to crack down on websites abroad engaged in piracy of movies, television shows and music.

The Combating Online Infringement and Counterfeits Act, which has the support of the entertainment industry but has been strongly criticised by digital rights and other groups, was approved by a vote of 19-0.

Senator Ron Wyden, a Democrat from Oregon, said that while online copyright infringement is a legitimate concern he planned to block the bill unless it was modified.