DENVER (AP) -- A Florida teen-ager pleaded guilty Wednesday to sending an e-mail message threatening to finish what the Columbine High School gunmen started when they killed 12 students and a teacher last spring.

Michael Ian Campbell, 18, answered 30 minutes of questions from U.S. District Judge Edward Nottingham before the judge accepted his guilty plea to one felony count of communicating a threat across state lines.

Campbell could get five years in prison and a $250,000 fine when he is sentenced April 28. Prosecutors agreed to recommend a lenient sentence, but Nottingham is not obliged to accept the recommendation.

Campbell, of Cape Coral, Fla., is accused of telling a Columbine student in a Dec. 15 e-mail that he would "finish what begun" at the high school last April, when Dylan Klebold and Eric Harris killed 12 students, a teacher and themselves.

Authorities who learned of Campbell's threat shut down Columbine two days before Christmas vacation as a precaution. Campbell was tracked to his Florida home via his Internet provider, America Online.

Campbell originally pleaded innocent. His lawyer, Ellis Rubin, outlined an ``Internet intoxication defense,'' claiming Campbell couldn't distinguish between reality and cyber-reality because of prolonged exposure to the Internet.