A Baltimore law firm filed a nationwide class action lawsuit against Facebook Friday, claiming the social network illegally tracked user activity on the Internet.

In its claim, the law firm Murphy P.A. said the company "repeatedly ignored" warnings from a user who noticed Facebook continued to track users' activities on the Internet even after they had logged off. Facebook finally confirmed the practice in September and promised to make corrections within 24 hours.

Facebook is in a quiet period ahead of its initial public offering.

"The days when online service providers can run roughshod over the privacy rights of their customers are over," said Murphy, P.A. Founding Partner William Murphy, Jr. said in a statement. "Companies that operate commercial websites, such as Facebook, need to realize the public is increasingly concerned about its privacy rights. Perhaps even more importantly, there is a growing community of security experts and bloggers that is extremely savvy about internet technology and committed to ensuring that people's privacy rights are respected and protected."

The company faces similar claims in Mississippi, Kansas and other states, but this is the first that seeks to bring a nationwide class against Facebook which could potentially involve every U.S. user who signed up for the service before Facebook updated its cookies and privacy policy. All of the lawsuits claim Facebook violates state and federal wiretap laws, among other accusations.

Murphy P.A. partnered with the San Francisco office of Girard Gibbs LLP to file the lawsuit in the U.S. District Court for the Northern District of California.