HARTFORD, Conn. – Geronimo's descendants have sued Skull and Bones — the secret society at Yale University linked to presidents and other powerful figures — claiming that its members stole the remains of the legendary Apache leader decades ago and have kept them ever since.

The federal lawsuit filed in Washington on Tuesday — the 100th anniversary of Geronimo's death — also names the university and the federal government.

Geronimo's great-grandson Harlyn Geronimo said his family believes Skull and Bones members took some of the remains in 1918 from a burial plot in Fort Sill, Okla., to keep in its New Haven clubhouse, a crypt. The alleged graverobbing is a longstanding legend that gained some validity in recent years with the discovery of a letter from a club member that described the theft.

"I believe strongly from my heart that his spirit was never released," Harlyn Geronimo said.

Both Presidents Bush, Massachusetts Sen. John Kerry and many others in powerful government and industry positions are members of the society, which is not affiliated with the university.

After years of famously fighting the U.S. and Mexican armies, Geronimo and 35 warriors surrendered to Gen. Nelson A. Miles near the Arizona-New Mexico border in 1886. Geronimo was eventually sent to Fort Sill and died at the Army outpost of pneumonia in 1909.

According to lore, members of Skull and Bones — including former President George W. Bush's grandfather, Prescott Bush — dug up his grave when a group of Army volunteers from Yale were stationed at the fort during World War I, taking his skull and some of his bones.

Harlyn Geronimo, 61, wants those remains and any held by the federal government turned over to the family so they can be reburied near the Indian leader's birthplace in southern New Mexico's Gila Wilderness.

Their lawsuit also names President Barack Obama, Defense Secretary Robert Gates and Army Secretary Pete Geren as defendants.

"I want them to understand we mean business," said Harlyn Geronimo, who lives in New Mexico. "We're very serious. We're tired of waiting and we're coming after them."

Neither members of Skull and Bones, who closely guard their secrecy, nor the Russell Trust Association, the organization's business arm for tax purposes, could not be reached for comment.

Justice Department spokesman Andrew Ames said the government will "review the complaint and respond in court at the appropriate time."

Fort Sill spokeswoman Nancy Elliot declined to discuss the lawsuit, but said officials have always maintained there is no evidence supporting the descendants' claims.

Yale officials declined to comment Wednesday, saying they had not yet seen the lawsuit. Spokesman Tom Conroy noted the Skull and Bones crypt is not on Yale property.

Membership into Skull and Bones marks the elite of the elite at the Ivy League school. Only 15 Yale seniors are asked to join each year.

Members swear an oath of secrecy about the group and its strange rituals, which include devotion to the number "322" and initiation rites such as confessing sexual secrets and kissing a skull. The atmosphere makes Skull and Bones favorite fodder for conspiracy theorists.

Its most enduring story is the one concerning Geronimo's remains, and in 2005, Yale historian Marc Wortman discovered a letter written in 1918 from one Skull and Bones member to another that seemed to lend validity to the tale.

The letter, sent to F. Trubee Davison by Winter Mead, said Geronimo's skull and other remains were taken from the leader's burial site, along with several pieces of tack for a horse.

"The skull of the worthy Geronimo the Terrible, exhumed from its tomb at Fort Sill by your club and Knight Haffuer, is now safe inside the T — together with is well worn femurs, bit and saddle horn," Mead wrote.

Wortman, however, has said he is skeptical the bones are actually Geronimo's.

Geronimo's descendants say in their lawsuit that they want to uncover any information that people know, but have been keeping to themselves.

"To assure that all existing remains of Geronimo and funerary objects are recovered by Geronimo's linear descendants, the Order of Skull and Bones and Yale University must account for any such articles that are or have been in their possession, or on their property, and persons with knowledge must provide any facts known to them concerning the claims," the descendants' lawsuit says.

If the bones at Yale aren't those of Geronimo, Harlyn Geronimo believes they belonged to one of the Apache prisoners who died at Fort Sill. He said they should still be returned.

Harlyn Geronimo wrote to President George W. Bush in 2006, seeking his help in recovering the bones. He thought that since the president's grandfather was allegedly one of those who helped steal the bones, the president would want to help return them.