Blanco told the AP in an April 2011 jailhouse interview that Drummond's senior management ordered that the two union organizers be killed. He said his conviction would allow them to "wash their hands" and get the U.S. lawsuit dismissed. That case remains in pre-trial motions.
The attorney representing the plaintiffs, Terry Collingsworth, applauded Castiblanco's order that prosecutors investigate Drummond's president, Garry Drummond, as well as a former mine security chief and two Colombians to determine whether they share any responsibility for the killings.
But Collingsworth also said he was not hopeful that the order would lead to a Colombian criminal prosecution as a different trial judge made the same recommendation when he convicted Blanco's former assistant, Jairo Charris, in the same murders in 2009. Charris was sentenced to 30 years.
In an unrelated development earlier Wednesday, Colombia's Environment Ministry indefinitely suspended permission for Drummond to load coal onto ships at its port near the city of Santa Marta.
The order, which paralyzes the company's exports, comes after Drummond dumped at least 500 metric tons of coal into the Caribbean over two days last month. A company statement released January 31, two weeks after the incident, said coal had to be transferred from one of its barges because it was in danger of sinking in bad weather. It said the coal was loaded into an empty barge but did not mention a spill.
A ministry official, Luz Helena Sarmiento, said permission would not be restored until Drummond presented a new contingency plan for emergencies.
Drummond produces 24 million tons of coal annually in Colombia, the bulk of its production. It claims more than 2 billion tons in reserves.
A Drummond spokeswoman in Colombia, Wilma Calderon, said the company had no immediate comment on the government action or the verdict.
Associated Press writers Vivian Sequera in Bogota and Frank Bajak in Lima, Peru, contributed to this report.
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