VILNIUS (Sputnik) - Washington did not give Lithuania the information on alleged illegal transfer of people across the border to be kept in secret jails run by the Central Intelligence Agency (CIA), the Lithuanian Prosecutor's Office said on Monday.

"In response [to the prosecutors' request], it was said that the United States is not able to supply the required information or responses to the questions of Lithuanian prosecutors," the statement of the Prosecutor's Office read.

According to the prosecutors, the preliminary trial is ongoing.

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In addition, the prosecutor's office stressed that "all circumstances can be determined and assessed only after all the necessary information has been collected."

The Lithuanian Prosecutor's Office noted that the requests were sent to the United States, Poland and Romania as well as other states in 2015. The pre-trial investigation into potential abuse of power was merged with the 2014 probe into human trafficking. Some countries replied to the requests, but the investigators did not receive any data that would help them make significant progress.

In May, the European Court of Human Rights (ECHR) ruled that Lithuania and Romania were knowingly hosting CIA secret prisons in 2000s.

In August 2009, US media reported that Lithuanian authorities allowed the United States to use a facility close to Vilnius to hold up to eight imprisoned members of al-Qaeda* terrorist group. A parliamentary committee in Lithuania carried out an investigation and concluded that the conditions for a secret detention facility were set up in Lithuania, and the organization's planes did land in the country in 2005 and 2006 without then going through obligatory customs checks. However, it was not proven whether any prisoners had been brought into the country or not.

In their turn, Lithuanian officials have said that there was no prison near Vilnius, but an intelligence support center.

*Al-Nusra, aka al-Qaeda in Syria, is a terrorist group outlawed in Russia and many other countries.