A Mastic man pleaded not guilty to attempted-murder charges yesterday in an alleged plot to burn down a house where four Level 3 sex offenders lived.  Police detectives, acting on a tip earlier this month, sent an undercover officer to befriend Donald Keegan, 36, a county employee and part-time landscaper who lives less than a mile from the home he planned to torch on Eleanor Avenue.  With a hidden camera with audio, the officer taped Keegan in the backyard of the target home.  I'm going to be lighting the side, Keegan told the detective.  The main concern is, I don't know how to explain this: I want them dead.  He planned to burn the house on the evening of September 9 using paint thinner and a road flare.  He was arrested that night.  He was charged with nine counts, including second-degree attempted murder and second-degree attempted arson, both felonies with maximum prison terms of 25 years.  He is being held on $1 million cash bail or $2 million bond.

(New York)