More than 30 Michigan schools closed for the holidays two days early, in part because the Mayan calendar predicts the world will end on Friday, an official said.

Matt Wandrie, superintendent for Lapeer Community Schools, said doomsday "rumors" are running rampant in several districts, adding to fears raised by last week's school shooting in Newtown, Conn.

"Given the recent events in Connecticut, there have been numerous rumors circulating in our district, and in neighboring districts, about potential threats of violence against students," Wandrie wrote on his website.

"Additionally, rumors connected to the Mayan calendar predicted end of the world on Friday have also surfaced," he added.

He noted that Twitter was lighting up with posts with sentiments like: "Friday would be a great day to go out w/ a bang."

The ancient predictions of apocalypse were a "secondary concern," with rumblings about violent threats against schoolchildren a bigger issue, he said.

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Wandrie said all rumors of threats had been "investigated and determined to be false" but were still a "serious distraction" for students heading into the holiday break, and parents were vowing to keep children home.

So officials from five districts in Lapeer County covering 33 schools decided to just scrap the last two days of classes, extracurricular activities and athletic events.

"Although we in the county are reluctant to cancel school because the rumors are unsubstantiated, we feel it is the most appropriate decision given the gravity of recent events and our present circumstances," he wrote.

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