The CIA held prisoners in a secret Lithuanian prison despite official denials, a detailed investigation by human rights investigators claims to show.
A dossier and briefing submitted to the Lithuanian prosecutor cross references newly obtained flight records with extracts from the US Senate Intelligence Committee report on CIA detention and interrogation, which was declassified in December.
Investigators working for human rights NGO Reprieve pieced together information on detainee movements, contained in the Senate report, with court records, freedom of information requests and documentation obtained from European air traffic management organization Eurocontrol, as well as other sources. The dossier substantiates allegations that the "Violet" black site referred to in the Senate Intelligence Committee report was a secret prison operated in Lithuania between 2005-6 as part of the US's post-9/11 extraordinary rendition program.
It also provides the firmest evidence yet that detainees were in fact held on the site, a claim which has consistently been met with Lithuanian denials and US silence.
Investigator Crofton Black told VICE News: "It's a very long winded cross-referencing process. It ends up showing that the flights that we've identified match the times that people were moved into and out of Violet.
"The documents match the movements the report describes and invoice numbers show the planes that were being contracted were on the same contract that was used to run renditions, basically."
Black added that it is not yet clear exactly who was held on the Violet site, but he is hopeful that it will become apparent following further investigation.
"This new dossier shows beyond reasonable doubt that CIA prisoners were held incommunicado in Lithuania, contrary to European and domestic law," he added.
Lithuanian prosecutors conducted their own investigation into secret CIA black sites on home soil, but shut it down in 2011 after one year. That followed a parliamentary inquiry, which found in 2009 that the CIA set up at least two secret detention centers after the September 11 terror attacks, reportedly without the knowledge of the country's prime minister.
State investigators said that the CIA had prepared a facility in a converted horse-riding school outside the capital Vilnius, but found no evidence that prisoners had been held in it.
In December, shortly after the release of the Senate Intelligence Committee torture report, the Lithuanian Prime Minister Algirdas Butkevicius pressed Washington to say whether it used his country to house one of the bases where it tortured prisoners.
"The US Senate report, to me, makes a convincing case that prisoners were indeed held at the Lithuanian site," lawmaker Arvydas Anusauskas, who headed the parliamentary inquiry, told Reuters at the time.
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Main image: Lithuanian lawmakers visited this converted horse-riding school, used as a training center by the Lithuanian state security agency, in 2009 as part of their inquiry into allegations that the CIA had operated black sites in the country. Image via Reuters.