The FBI says an apparent attempted bombing at a Colorado shopping mall was not likely related to the 12-year anniversary of the shootings at nearby Columbine High School.
FBI Denver spokesman Dave Joly Monday says investigators have found a motive but aren't releasing additional information.
The FBI on Sunday alerted field offices covering all 50 states and Puerto Rico to be on the lookout for 65-year-old Earl Albert Moore.
Moore has been named the suspect in Wednesday's fire at Southwest Plaza Mall, about 2 miles from Columbine, where 12 students and a teacher were killed in 1999.
Authorities discovered a pipe bomb and two propane tanks after the fire, raising fears that the incident was timed to coincide with the anniversary.