7 Accused of Plot to Kill Mexican Candidate Colosio : Inquiry: Special prosecutor implicates organizer of presidential front-runner’s Tijuana security. Five suspects have been arrested; two others remain unidentified.

At least seven people--including a former police detective who organized the Tijuana security detail--were involved in a conspiracy to assassinate Luis Donaldo Colosio, the slain ruling party presidential candidate, government officials said Monday.

Based on videotapes, photographs and testimony, the special prosecutor assigned to investigate the case has concluded there was “a mutual and prior agreement to commit the crime,” according to a statement, which did not address the question of why Colosio was killed.

Five of those believed to be involved in the conspiracy have been arrested, including four men assigned to the Colosio campaign’s local security detail; two other suspects remain unidentified.

As the list of accused conspirators grew Monday, Mexicans became increasingly eager to know where the investigation will lead. Suspicions have ranged from drug traffickers to groups connected with the guerrillas in southern Mexico to Colosio’s own party, the Institutional Revolutionary Party, or PRI, which has ruled Mexico for 65 years.

“The investigation must continue,” said Jose Luis Perez Canchola, the human rights ombudsman in Baja California. “I believe that the action involves more than just this group. . . . These are people who take orders.”

Mario Aburto Martinez, who authorities say shot Colosio, was apprehended at the scene; Tranquilino Sanchez Venegas, an alleged accomplice and security guard, was arrested last week. Officials said three others have been arrested in connection with Colosio’s murder at a Tijuana campaign rally March 23:

Rodolfo Rivapalacio, a former member of the state judicial police who headed burglary investigations. He was one of several former high-ranking officers affiliated with the PRI who organized a 45-member crowd control team.

The team--which was separate from Colosio’s federal guards, who are the Mexican equivalent of the U.S. Secret Service--was made up of former police officers, some with checkered records. Rivapalacio was also a member of the state secret police, according to the magazine Proceso, and a former bodyguard for Margarita Ortega, who became the first PRI gubernatorial candidate ever defeated when she lost to Baja California Gov. Ernesto Ruffo Appel in 1989.

Vicente Mayoral Valenzuela, who is believed to have opened a path through a crowd of well-wishers for the gunman to move toward Colosio. Mayoral, 60, is a former homicide commander of the state judicial police. Aburto’s relatives said he recruited the shooting suspect into a shadowy political group that may be connected to the assassination. Mayoral had been arrested just after the shooting but was then released.

Rodolfo Mayoral Esquer, 23, Mayoral’s son, is accused of pushing and disturbing Col. Federico Antonio Reynaldos de Pozo, who was second in charge of the federal security forces. That distracted him and diminished the effectiveness of security measures moments before the gunman shot Colosio at point-blank range. Family members assert that both father and son are innocent. “This shows how easy it is to destroy two lives,” said the elder Mayoral’s daughter, Aracely. “They are grabbing people as scapegoats.”

Sanchez and the younger Mayoral were seen speaking with Aburto throughout the rally, according to a statement released by special prosecutor Mario Montes.

Two other men, whose names were not disclosed, are also alleged conspirators. One suspect is said to have moved in front of Colosio and fallen on the ground to prevent him from advancing, allowing Aburto to position himself. The second suspect, who wore glasses, cleared a path toward the candidate’s left, then hunched down just before Colosio was shot.

It was unclear Monday if the two unidentified suspects included other members of the security detail, known as Grupo Tucan, which has come under intense scrutiny.

As Ruffo noted Monday, some of the Tijuana guards provided by the local PRI were dismissed from local law enforcement because of dubious conduct. “There are names on the list of people who were fired for misconduct,” the governor said at a news conference.

Echoing widespread sentiment that the conspirators acted on orders from someone more powerful, a Tijuana human rights activist said investigators should examine how and why the PRI chose its security guards.

“These are people who do not have the capacity or the motivation to organize such an act,” said Victor Clark Alfaro, director of the Binational Center for Human Rights. “The leaders of the PRI have to explain why this very questionable security group was chosen. The leaders of the PRI have direct responsibility because they organized the security.”

The political ties of Rivapalacio and the others intensify suspicions of a politically motivated plot within the ruling party, Clark and others assert.

Meanwhile, the southern guerrillas--who call themselves the Zapatista National Liberation Army--have expressed concern that Colosio’s death will be blamed on them, especially since Aburto reportedly has said he fired on the candidate because he was upset about the violence in Chiapas state. The Zapatistas have denied responsibility for the attack.

The rebels have halted consultations on a government peace proposal and prepared for an assault as a result of the accusations. In weekend editions of Reforma, rebel leaders invited the new PRI candidate, Ernesto Zedillo, to visit guerrilla-held territory and talk directly with them.

The Zedillo campaign has not responded publicly to the invitation.

Darling reported from Mexico City and Rotella from Tijuana.