Ness Motley, the South Carolina law firm that represented states in their legal fight against the tobacco industry, is going after a new set of defendants: the people and institutions it says bankrolled the Sept. 11 terrorist attacks.

More than 500 family members and survivors of the attacks filed suit Thursday in U.S. District Court for the District of Columbia, according to the plaintiffs’ announcement. CNN put the number at more than 600 family members, plus some firefighters and rescue workers. The plaintiffs seek damages large enough to punish the defendants and deter them from ever again funding terrorism, the announcement said.

The defendants include seven international banks; eight Islamic foundations, charities and their subsidiaries; individual financiers; the Saudi bin Laden Group; three Saudi princes; and the government of Sudan, the announcement said. The plaintiffs call themselves 9/11 Families United to Bankrupt Terrorism.

The case, Burnett v. Al Baraka Investment and Development Corp., charges the defendants with 15 counts, including racketeering violations, wrongful death and conspiracy. Among the princes named are Prince Turki al Faisal al Saud and Prince Sultan bin Abdul Aziz al Saud. The complaint alleges that Prince Sultan has given at least $6 million since 1994 to four charities that finance al Qaeda, according to the announcement. None of the allegations has been tested in court. Officials from the Saudi Embassy did not return a call for comment, CBS News reported.

Ron Motley, the attorney for the plaintiffs, said in the announcement that the plaintiffs have “every reason to believe that the defendants in this action are still funneling, laundering and sending money to al Qaeda.”

Motley’s legal team also includes Allan Gerson, who helped Pan Am Flight 103 families pursue claims against Libya, and investigator Jean-Charles Brisard, the announcement said.

A 1999 Washington Post article, reprinted in the Congressional Record, described Ness Motley Loadholt Richardson & Poole as a South Carolina-based firm that had earned millions of dollars representing states in the tobacco settlement.

The plaintiffs come from 20 states, including South Carolina, plus Washington, D.C., Puerto Rico and five other countries, the announcement said.

“It’s up to us to bankrupt the terrorists and those who finance them so they will never again have the resources to commit such atrocities against the American people as we experienced on September 11,” said Deena Burnett, whose husband, Tom, died aboard United Flight 93, CNN reported.

Terry Strada, whose husband, Thomas, died at the World Trade Center, said in the announcement that families must act against terrorism, “and this is what we and our counsel, Ness Motley, are doing.”