Prosecutor Links Ruling Party to Mexican Assassination : Investigation: Top PRI officials are accused of trying to block probe into September killing of their secretary general.

The chief prosecutor investigating a web of political intrigue behind the September assassination of Mexico’s second-ranking ruling party official heightened the drama Tuesday, linking the killing directly to the Institutional Revolutionary Party and publicly accusing the party’s top two bosses of trying to block the probe.

Sending new shock waves across Mexico’s already turbulent political landscape, Deputy Atty. Gen. Mario Ruiz Massieu charged that the ruling party’s president, Ignacio Pichardo, and its new secretary general, Maria de los Angeles Moreno, “were more concerned with trying to defend the criminals than trying to solve the case of their (slain) secretary general.”

He offered few specifics to back up the charge, but the prosecutor said he is convinced that the Sept. 28 murder of party Secretary General Francisco Ruiz Massieu was engineered by key members of the PRI, as the ruling party is known.

Prosecutor Ruiz Massieu is the brother of the slain secretary general, who was gunned down outside a downtown Mexico City hotel after a breakfast meeting, and the veteran prosecutor’s investigation has uncovered what he has characterized as a broad conspiracy reaching higher into the ruling party with each new witness’s testimony.

On Tuesday, though, it was clear that the prosecutor--a ruling party member in good standing before he took on the probe into his brother’s death--had struck at the heart of the political force that has ruled Mexico for the last 65 years.

“It is clear that the country has not had a murder with such important political characteristics, in which it was so totally clear, in my view, that it involved people of the PRI,” he declared in a late-night television interview that ignited the controversy.

Soon after the program aired, the ruling party issued an urgent six-point statement rejecting the allegations as “without foundation.” The statement, signed by party President Pichardo, declared the party’s “total support for expediting the investigation . . . and its commitment to cooperate.”

But Pichardo, in deflecting Ruiz Massieu’s charges that he was stonewalling the probe, criticized the prosecutor for leveling the accusations outside the legal process.

In a separate communique issued after Ruiz Massieu’s charges were aired on the private network Television Azteca late Monday night and published nationwide Tuesday, the PRI’s Commission on Honor and Justice announced that it had taken action on an allegation Ruiz Massieu made in the case more than a month ago--a delay the prosecutor cited on the program as one indication that the party had been uncooperative at best.

The commission declared in its statement that it had decided--apparently after weeks of deliberation--to recommend the expulsion from the party of renegade PRI legislator Manuel Munoz Rocha. He has eluded a national and international police hunt since Ruiz Massieu, acting on testimony from more than a dozen suspects in the case, named the legislator as one of the chief architects of his brother’s killing.

But the party made no comment on Ruiz Massieu’s additional speculation in the television interview that Munoz Rocha may be a link between his brother’s slaying and the assassination in March of PRI presidential candidate Luis Donaldo Colosio--potentially an even more explosive allegation. The prosecutor said the legislator was in charge of Colosio’s national campaign events, including public rallies such as the one in Tijuana where Colosio was gunned down. The investigation into that assassination is also continuing.

Despite the ruling party’s damage-control efforts, the developments in the probe into Mexico’s second major political assassination in six months could not have come at a worse time for Mexico’s president-elect, Ernesto Zedillo.

Zedillo is in the midst of a campaign to reinforce election pledges of ruling-party reform, which he launched a week ago after he was confirmed as president-elect during a 17-hour legislative debate certifying the results of the Aug. 21 elections. The polls gave Zedillo just over 50% of the vote, the lowest plurality in ruling party history, and most analysts question his ability to reform the party with so small a mandate.