Initially authorities believed that Yeom Pyo Lee helped suspected gunman James Egan Holmes pull off his shooting massacre at an Aurora, CO movie complex where 12 people were killed during a midnight showing of Batman: The Dark Knight.
Lee is now in the clear after police questioned him about his knowledge of Holmes.
Lee was sought by officials after police received a message from his telephone threatening violence if James Holmes was not released from police custody.
According to Fox 31 Denver, Lee, who is believed to be a student on the PhD course at the University of Colorado, Denver, from which Holmes recently dropped out, was released without charge after questioning.
He came to the attention of the police when 'someone called from [his] phone and threatened violence if Holmes is not released.'
Lee’s neighbors in Aurora said that there was a heavy police presence around the street where he lives, and officers repeatedly questioned residents as to his whereabouts.
Police finally talked to him on Saturday evening, but after the interview released a statement saying, "There is no reason to believe that he is involved."
Lee, who is originally from South Korea, earned a master's degree in biomedical science from Hallym University, a private college in the city of Chuncheon, before moving to Colorado to study for his doctorate.