A Long Island high-school student who decorated his bedroom with pictures of the Columbine HS massacre nearly blew himself up making a pipe bomb, authorities said.

Vincent Pizzonia, 17, a senior at North Babylon HS, severely injured his hand Monday in an explosion while allegedly building a bomb with gunpowder taken from bullets belonging to his father.

The student claimed he wanted to blow up the bomb in his back yard, police said. But authorities got worried after finding pictures of the 1999 Columbine horror on his bedroom wall.

No explosives were found at North Babylon HS.