Nearly 30 years after an elite Guatemalan military force raped and slaughtered residents of a tiny village, US and Canadian authorities are closing in on some of the alleged perpetrators.
The arrest of four ex-soldiers in a little more than a year has raised hopes among advocates of victims' relatives that at least one might stand trial for the killings.
Human rights advocates are pinning their hopes on the prosecution of Jorge Sosa Orantes, who was arrested in January in Canada on US charges of lying on his citizenship application about his ties to the Guatemalan military.
In the United States, Sosa is only charged with immigration violations - not carrying out the 1982 massacre in the village of Dos Erres.
Activists in Canada, where he is jailed, are now pressing their government to try him for crimes against humanity, noting the case has languished in Guatemalan courts.
``This has transcended to a global level,'' said Aura Elena Farfan, director of the Association of Relatives of the Detained and Disappeared in Guatemala.
``The US, Canada, Spain and other countries, I consider these to be democratic countries where justice is truly applied as it is. That's a big advantage, unlike here, where there's political intervention.''
The US is the latest player to join the long-standing cases that have been brought before courts across the globe in search of justice.
In December 1982, members of an elite military unit known as the ``kaibiles'' stormed Dos Erres in search of stolen weapons and systematically killed the men, women and children. Soldiers bludgeoned villagers with a sledgehammer and threw them down a well and raped women and girls before killing them, court papers show.
At the time, the kaibiles were tracking an armed insurgency by guerrillas opposed to the military government.
The civil war in Guatemala claimed at least 200,000 lives before it ended in 1996. The US-backed army was responsible for most of the deaths, according to the findings of a truth commission set up to investigate the bloodshed.
The Guatemalan government opened an investigation into the killings in Dos Erres in 1994 and unearthed 162 skeletons. Authorities issued arrest warrants for 17 former kaibiles but for years the cases languished, prompting victims to seek justice abroad.
In Spain, Rigoberta Menchu, who lived in Guatemala and won the Nobel Peace Prize in 1992, filed a lawsuit accusing former top Guatemalan officials of terrorism, genocide and torture. The suit was eventually expanded to include the massacre at Dos Erres.
Victims' relatives took their case to a commission of the Organisation of American States. In 2009, the Inter-American Court of Human Rights ordered Guatemala to investigate and prosecute the perpetrators of the massacre and sanction those who had delayed justice.
Since then, three kaibiles have been arrested in Guatemala but most remain at-large, Farfan said. International human rights activists hope US involvement in the cases might prod Guatemalan authorities to action - even though Washington has only charged the four former soldiers, including Sosa, with immigration violations.
One of them, Gilberto Jordan, pleaded guilty last year to lying on his US citizenship application and was sentenced to 10 years in federal prison after admitting to investigators that he threw a baby down a well during the carnage.
``I'd like to see a conviction for mass murder, for genocide,'' said Naomi Roht-Arriaza, a law professor at University of California, Hastings College of the Law, who has written about the international prosecution of human rights violations in Guatemala.
``But it's a big improvement over what used to happen,'' she said, noting that alleged rights violators were often simply deported to their home countries and then vanished.
Court papers filed with the Inter-American Court alleged that Sosa was one of four officers at a meeting in December 1982 where kaibiles were told they had orders to destroy the village of Dos Erres and kill ``everything that moved.''
Roht-Arriaza said she believes the US isn't applying its own war crimes law to Sosa's case because the massacre pre-dates the legislation and isn't applying international or common law because authorities have traditionally been risk averse and want to assure a conviction.
Justice Department officials declined to comment on the details of the Dos Erres prosecutions because the Sosa case is still pending, but said the government uses different tools to crack down on human rights violators, including immigration law.
``The injustice of atrocities such as Dos Erres does not fade with the passage of time,'' said Assistant Attorney General Lanny Breuer, who heads the Department's criminal division. ``As demonstrated by the case of Gilberto Jordan, our commitment to pursuing justice does not either.''
It was not immediately possible to reach Sosa, who was arrested in Alberta, Canada on January 18 while visiting his parents. The Southern California martial arts instructor holds Canadian and US citizenship.
His attorney, Alain Hepner, declined to comment on the allegations but said Sosa currently faces only one extradition request - that from the United States.
``As it stands right now, the extradition is only to the United states for allegations of misleading or falsifying or giving untruthful statements,'' Hepner said.
The case against the kaibiles in the United States came roughly a year after Immigration and Customs Enforcement expanded a unit that tracks down human rights violators. Officials at the unit declined to discuss the Guatemalan cases or reveal what prompted them to look into the kaibiles more than a decade after some entered the United States.
In February 2010, immigration agents arrested former soldier Santos Lopez Alonzo at a nightclub parking lot in Houston and charged him with re-entering the country illegally after he had been deported more than a decade earlier, court papers show.
A month later, federal prosecutors moved to have Lopez declared a material witness in the case investigators had been building against three of his fellow soldiers, including Sosa and Jordan, according to court filings.
Lopez told investigators he witnessed kaibiles killing villagers by covering their faces with a rag and then hitting them in the head with a mallet. He also said he saw Sosa killing individuals at the village well and that Jordan was at the school where kaibiles were trained in 1982, court papers show.
Lopez also said he saw former military instructor Pedro Pimentel Rios - another former kaibil sought by the US - in Dos Erres during the massacre. Pimentel was arrested by US immigration authorities in May and is currently in federal custody fighting efforts to deport him, claiming he wasn't at the massacre and will face persecution at home.
Lopez told investigators his primary duty during the Dos Erres massacre was guarding women and children at the village school before they were taken to the well to be killed. According to allegations filed at the Inter-American court, Lopez adopted a boy who survived the massacre.
Lopez is being held by US authorities and could not be immediately reached.
Matt Eisenbrandt, legal coordinator for the Canadian Centre for International Justice, said groups like his are pushing for Canada to carry out its own investigation into the massacre before turning Sosa over to US authorities for prosecution of a less serious crime.
Advocates are hopeful because Canada has more expansive laws than the United States and can prosecute individuals for war crimes, crimes against humanity, or genocide, Eisenbrandt said. Canadian prosecutors declined to comment on the case.
``There has to be full accountability here,'' Eisenbrandt said. ``Just sending him to the United States on fraud charges, even if he got the maximum sentence, would not be a sufficient punishment.''