SAN SALVADOR — For more than a week, Guatemalans and Salvadorans have been in the grip of a murky and gruesome mystery story born of Central America's criminal underworld.
It began on the night of Feb. 19, with an SUV burning on a rural road outside Guatemala City. The charred bodies of three Salvadoran legislators and their driver were found at the scene. Among them was Eduardo Jose D'Aubuisson, the son of one of El Salvador's most notorious right-wing leaders.
On Sunday night, the latest chapter played out at a Guatemalan prison, when four officers from a top Guatemalan police unit were slain in their cells three days after they had been arrested and charged with killing the legislators.
Police and government officials in El Salvador and Guatemala said the case may have exposed an unsettling link between drug traffickers and the security and political elite of the countries.
On Friday, Guatemalan President Oscar Berger said drug traffickers were behind the killings of the legislators and promised a "thorough purge" of corrupt elements in the Guatemalan police force.
Berger said he would take the extraordinary step of requiring dozens of high-ranking police and government officials to take polygraph tests, including, "if necessary," Interior Minister Carlos Vielmann, the country's top security official.
The four police officers killed Sunday were all members of Guatemala's organized-crime unit, and included the unit's director, Luis Arturo Herrera. There were conflicting reports as to how they were killed.
Some media reports said an armed "commando" unit had entered the maximum-security prison about 40 miles outside Guatemala City. The assailants reportedly disarmed the guards, then slit the throats of the arrested officers.
Other reports said inmates in the prison killed the men in retribution for their actions as police officers.
In neighboring El Salvador, some saw a conspiracy.
"The killing of these officers shows there are more people involved" in the assassination of the legislators, said Rodrigo Avila, head of El Salvador's national police. "They wanted to silence these officers, who were part of a very powerful [criminal] organization.... They're trying to close a Pandora's box."
Avila said top officials in Guatemala's national police had joined forces with an organized-crime group involved in a variety of illicit activities, including drug trafficking, immigrant smuggling and money laundering.
"We are very worried that the top levels of the [Guatemalan] police appear to have been infiltrated by organized crime," Salvadoran Minister for Security and Justice Rene Figueroa said.
Salvadoran officials say they don't know precisely how or why the legislators were slain.
The legislators left San Salvador in a caravan with other lawmakers on the morning of Feb. 19, headed for a meeting in Guatemala City of the Central American Parliament, a body that advocates and regulates regional economic cooperation.
They were last seen alive in Guatemala City on the day of their disappearance, after leaving behind their Guatemalan police escort. Their bodies were discovered on a farm 25 miles outside the city, with gunshot wounds and burned beyond recognition. At least two of the men may have been burned alive, according to news reports.
Guatemalan authorities said the method of the attack clearly suggested it was a "message" killing.
Besides D'Aubuisson, the 32-year-old son of Roberto D'Aubuisson, the late founder of El Salvador's ruling Nationalist Republican Alliance, the dead included two other legislators from the right-wing party, William Pichinte and Jose Ramon Gonzalez.
Salvadoran President Tony Saca called the men national heroes who had died "in the cause of freedom."
But on Sunday, the Guatemala City newspaper Siglo XXI quoted an unnamed Guatemalan police official who said the killers and victims were linked "with a drug trafficking organization made up of Guatemalans and Salvadorans, among them a contact with a lot of political influence" in El Salvador.
The crime was the result of "a business deal gone sour, which is unforgivable among drug traffickers," the police official said.
In El Salvador, the idea that the scion of one of the nation's leading right-wing families may have been involved in drug dealing was unpalatable. Salvadoran police floated a different theory: mistaken identity.
The conservative newspaper El Diario de Hoy quoted Salvadoran police who said the slain lawmakers had been confused for "Colombian drug dealers" and killed when their assailants failed to discover cash or drugs.
The arrested police officers told investigators that they had been contracted by a group of Guatemalan drug traffickers linked to Salvadoran organized crime. But they would say no more about their orders, because, as one of them said, "I'd rather commit suicide than talk."
Times staff writer Tobar reported from Mexico City and special correspondent Renderos from San Salvador.