Four U.S. Postal Service workers have sued the maker of an antibiotic they took during the anthrax scare two years ago, saying the drug caused harmful side effects.

The lawsuit filed in Superior Court on Friday alleges that Bayer Corp. failed to disclose data that Cipro could damage nerves and tendons.

The lawsuit, which seeks class-action status, also accuses three New Jersey hospitals of failing to provide warnings, perform exams or offer alternative medications.

Thousands of people who may have been exposed to anthrax spores were encouraged to take Cipro or doxycycline, another antibiotic. Anthrax spores were found in mail or mail processing facilities in the District of Columbia, New York, New Jersey, Florida and Connecticut.

The anthrax attacks killed five people and sickened 17 nationwide. No arrests have been made.

Representatives from Bayer Corp., the Pittsburgh-based U.S. subsidiary of German pharmaceutical giant Bayer AG, and the New Jersey hospitals said they were unaware of the lawsuit and had no immediate comment on it.

Last month, after a Philadelphia law firm announced plans for a similar lawsuit, a Bayer spokeswoman said Cipro's label warns of side effects.

The four New Jersey postal workers suing Bayer worked at the Hamilton postal facility, where at least four anthrax bacteria-laden letters with Trenton postmarks were processed. That building has been closed since 2001.

Mail handler James Sherman said he developed pain in his elbows, knees and groin shortly after taking Cipro.

"I later complained to the hospital," Sherman told the Star-Ledger of Newark. "But now, I walk like I'm crippled all the time. I never had these aches and pain before."