FARMINGTON, N.H. (AP) — New Hampshire firefighters say a high school student playing with his iPod in class caused the battery to explode when he dropped the device, sending light, hazy smoke through the room.

Farmington Fire Chief Rich Fowler says about 18 students at Farmington High School were evaluated. Some complained of headaches, dizziness and nausea.

Two students were checked out at a hospital as a precaution.

Fowler says the incident, which happened at about 9:30 a.m.

Tuesday, was confined to the classroom.

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