A janitor pleaded not guilty to murder Friday in the death of a Northern California school principal who was shot after sending the suspect home to "cool off" over a personnel dispute.

John Luebbers, 44, was charged after telling investigators he fired two shots and struck Principal Sam LaCara, 50, in the office at Louisiana Schnell Elementary School in Placerville, police said. Luebbers told police that LaCara had fired him Wednesday just days after the two friends had gone golfing.

School officials, however, said Luebbers had only been sent home for the day after the two had an argument about the district's selection of a new nighttime custodian. Luebbers entered a not guilty plea during his arraignment Friday afternoon and was held without bail. Family members attended the hearing but did not address reporters outside