The father of the Afghan-born airport shuttle driver from Aurora who is accused of plotting an al Qaida bomb attack on New York City has pleaded not guilty to charges of conspiring to help his son. Fifty-three-year-old Mohammed Wali Zazi was transferred from Denver to Brooklyn, New York, where he appeared briefly in court to hear the charges he faces of conspiring to alter, destroy, and conceal evidence, reports Reuters , which points out that the elder Zazi could see up to 20 years in prison. He was arrested last month in Denver and placed under a permanent order of detention in New York by a judge yesterday. His son, Najibullah Zazi, 24, a former New York coffee vendor who later moved to Colorado, was arrested in September and has pleaded not guilty to plotting a bombing. Investigators say Mohammed Wali Zazi lied to the FBI when he was asked if he had spoken to anyone on the phone about whether his son was in any trouble with authorities, writes 9News  (read a copy of the indictment ). Authorities believe his son wanted to attack New York's transit system---a terrorism case Attorney General Eric Holder has called the most serious since the September 11, 2001, attacks (via The Associated Press ). A New York imam and two men who attended a New York City high school with Najibullah Zazi have been charged, as well. All have pleaded not guilty.