05/06/2011 05:00 pm ET Updated Jul 06, 2011

Earl Albert Moore Pleads Not Guilty To Mall Bomb Near Columbine

An ex-convict accused of planting an explosive device near a Denver-area mall pleaded not guilty to charges of arson and possession of a destructive device during a Friday hearing.

Earl Albert Moore, 65, was caught on Southwest Plaza Mall surveillance video leaving a homemade pipe bomb and two propane tanks near an employee entrance of the mall. The bomb and tanks were found after a fire, but they didn't detonate. No injuries were reported.

The fire occurred on the 12th anniversary of the shootings at Columbine High School, which is about two miles from the mall. Authorities also noted that the times of the mall fire and the Columbine shootings were similar, as was the use of a pipe bomb and propane tanks, which were used during the attack at the school in 1999 that killed 12 students and a teacher.

Moore was apprehended by authorities six days after the fire, after being spotted by a woman shopping at a King Soopers in Boulder.

News 9 reports that Moore was indicted by a federal grand jury Friday for arson and use of a destructive device during a crime. If convicted on the arson charge, he will face no less than five years and no more than 20 years in federal prison and a fine up to $250,000. If convicted of use of a destructive device, he will be fined $250,000 also.

The FBI still hasn't released information as to Moore's motive, but say it's unrelated to Columbine.