GREEN BAY, Wisconsin (AP):

Three teens accused of helping to plan an attack on a Wisconsin high school similar to Colorado's Columbine school massacre in which 12 people were killed years earlier pleaded no contest yesterday to conspiracy charges.

William Cornell, 18, pleaded no contest to conspiracy to commit homicide, possession of explosives for unlawful purposes and possession of a short-barrelled shotgun.

Shawn Sturtz, 18, pleaded no contest to conspiracy to commit first-degree homicide, while Bradley Netwal, 19, pleaded no contest to conspiracy to damage property with explosives.

The three were accused of making bombs and collecting guns to carry out the attack at the north-eastern Wisconsin school. They were arrested last fall after a fourth teen, who was not charged, toldan associate principal at East High School about the plot.