As early as November 1975, the FBI was aware of a conspiracy to assassinate Juan Mari Brás — then leader of the Puerto Rican Socialist Party who was running for governor — and failed to inform him or his family of the plot, while his 23-year-old son Santiago “Chagui” Mari Pesquera was murdered March 24, 1976 in an apparent offshoot of the planned political assassination, according to declassified FBI documents.

When asked to comment, local FBI spokesman Harry Rodríguez referred the matter at press time to Miami FBI field office spokeswoman Judy Orihuela because “this is the office that generated the documents.”

For Rosa Mari Pesquera — the political leader’s daughter and sister of the Santiago Mari Pesquera — the two events are clearly linked. “Juan Mari Brás is from a generation of men and women who were not afraid. The logical thing then is to attack that person’s heart so that their head will fail,” Mari Pesquera said, while calling on the FBI to hand over all documents related to her father and her brother’s killing 34 years ago as well as Puerto Rico Justice Department to reopen its investigation into the case.

Mari Pesquera sent copies of the declassified documents to Justice Secretary Antonio Sagardía in a letter dated Nov. 29 asking him to continue the investigation to find the masterminds behind her brother’s murder.

While Henry Walter Coira Story was convicted of the murder and served 10 years in prison, Mari Pesquera said information indicates that he did not act alone. “Coira was used to murder my brother and cover up the true masterminds,” she said.

Puerto Rico’s Commission for Truth and Justice, which is dedicated to investigating the slew political assassinations that occurred in Puerto Rico during the 70s and 80s, revealed the information Wednesday. The group found the documents on the Internet as part of its investigation into the murder of Carlos Muñiz Varela by right-wing Cuban dissidents living in Puerto Rico, commission member Raúl Alzaga said.

“If the parties in both had not been linked, we never would have found these documents,” Álzaga said, adding the FBI has always denied the existence of documents related to assassination plots against Mari Brás or his son. “What we want to know is if the FBI stopped the plot to assassinate Mari Brás and whether this is related to Chagui’s murder.”

The first document — file no. 105-22478 dated March 29, 1976 and declassified in 1999 — states that on Nov. 5, 1975 a source known as MM T-1 advised that: “[Rafael] Pérez Doreste said that Reinol Rodríguez of San Juan, Puerto Rico has in the past been discussing the possible assassination of Juan Marie [sic] Bras, who is Secretary General of Partido Socialista Puertorriqueño and who is also very pro-Castro, and that Frank Castro has authorized Rodríguez to work on a plan to kill Juan Marie Brás. No further details were mentioned regarding this possible plan.”

“Currently Reynol Rodríguez González lives in Miami and is the military chief of the paramilitary Cuban exile group Alpha 66. Frank Eulalio Castro Paz lives in the Dominican Republic,” Alzaga said.

The document is an FBI memo to the U.S. Justice Department discussing Frank Castro’s criminal activities, which include the placing of a bomb on Russian ship Maxim Gorki while it was in San Juan harbor and plans to bomb Cuban merchant ship.

The second document is another FBI memo to the U.S. State Department — file no 105-21892 and dated Aug. 25, 1976 — detailing the agency’s investigation of right-wing Cuban paramilitary group the National Cuban Liberation Front. The second page of the memo lists actions by the group that goes by the Spanish initials FLNC.

Among the actions listed was the following dated January 1976 in Puerto Rico: “Assassination plot against the leader of the Socialist Party of Puerto Rico. Rifles and telescopic scopes sent to Puerto Rico.”

“This brings us closer to what we have said for 34 years … They did not act to warn my father and my family that we were in danger,” Mari Pesquera said.

“We have asked the FBI for the information. Here is the proof that an act of aggression was being planned against Juan Mari Brás. They have the information. They have it. They should give it [out],” Mari Pesquera said.

Based on the new findings, Gervasio Morales Rodríguez, director of Claridad newspaper that Mari Bras helped found, filed a freedom of information request with nine federal agencies seeking copies “of all records, files, documents, information, recordings. videos, etc. — agency originated records or records received by agency — concerning to and containing information about Juan Mari Brás, (his wife) Paquita Pesquera Cantellops, and Santiago ‘Chagui’ Mari Pesquera.”

“I hope that President Obama and Attorney General Eric Holder honor

their promise to be more open in Freedom of Information Act requests,” Morales said.

Agencies called to disclose information are: FBI, National Security Agency, CIA, Defense Department, Navy, Army, Defense Intelligence Agency, Office of the Director of National Intelligence, Coast Guard, and Federal Aviation Administration.

Santiago wasn’t the only child who was targeted, Morales said in the letter. “An attempt to murder Juan Raúl Mari Pesquera, another son of Juan Mari Brás and Paquita Pesquera occurred on Jan. 25, 1980. U.S. Navy Lieutenant Alex de la Zerda, at the time U.S. Navy’s liaison officer to the civilian community on the island of Vieques in Puerto Rico, placed a bomb in a Vieques Air Link flight being piloted by Mari Pesquera,” Morales says in the letter.

The letter also indicates that former Gov. Aníbal Acevedo Vilá wrote to then President-elect Barack Obama on Dec. 29, 2008 appealing for the new president to intervene with the FBI to declassify all information related to the case. Morales quotes the Acevedo Vilá’s missive to Obama: “The facts surrounding this murder, the numerous threats that Mari Brás and his family received before the boy was killed, and the long history of political persecution that Mari Brás has experienced throughout his life, strengthen the theory that the motive of the perpetrators of this assassination was political, in order to harm the head of the Socialist Party and, therefore, the independence movement in Puerto Rico.”