The Pulitzer Committee says Oregonian reporter Les Zaitz undertook "personal risk to him and his sources" and "revealed how lethal Mexican drug cartels infiltrated Oregon and other regions of the country." The story begins:

For more than a day, the plastic orange toolbox sat on the lawn under a cherry tree, a few paces from the sidewalk.

No one passing the Canby home took notice. Not the runners. Not the dog walkers. Not the kids riding by on bicycles.

Then curiosity drew a 31-year-old landscaper who had come to the home just after sunset to help a friend move. Ivan Velasco Rodriguez poked the toolbox with a wooden rake handle.

The pipe bomb lurking inside exploded. Metal shards flying at bullet speed fatally injured Velasco Rodriguez and slammed into surrounding homes. Pieces fell on roofs two blocks away.

In a painstaking investigation, Zaitz explores the links between the blast and explosions that rocked the town of Moses Lake in Central Washington in 2008. Read the whole, chilling thing.