A 40-year-old bus driver was shot and killed near Washington Tuesday, and police are treating the case as the latest in a series of sniper attacks that have terrorized the region.

The driver was shot in the chest as he stood on the steps of a commuter bus. He died after being rushed to the hospital.

The shooting occurred in the Maryland suburbs, just north of Washington. Although there is no definitive link yet to the series of sniper attacks that have killed nine people and wounded three others, police are treating this latest shooting as if it is related.

Police quickly set up a widespread dragnet on local roads, throwing Washington's morning rush hour into chaos.

On Monday, investigators urged a man they believe to be the sniper to call them back. Police said an earlier message was garbled.

The sniper attacks have terrorized the Washington area, leaving many residents fearful to go about every day activities like shopping or putting gas in their cars.