A panel of judges in Albania has accused the United States of "interference" in the trial of two senior police officers acquitted this week on murder charges over the 2011 death of four anti-government protesters.

The three judges cleared the suspects after considering evidence gathered with the assistance of U.S. forensic experts. The U.S. Embassy in Tirana expressed dismay over the verdict.

In a statement Friday, the judges accused the American embassy in Tirana of "prejudging a fair, legal, and impartial process."

U.S. Ambassador Alexander Arvizu replied in a statement that the "charge is simply without foundation." He added that American involvement in the case followed a request from Albanian authorities.