BOISE - Monday was a deadly day on Idaho roads and highways throughout the state for motorcyclists.

Four people were killed, including two from Boise, in three separate crashes.

The first crash, Idaho State Police says, occurred on Highway 55 near Banks. Police say Richard Schroeder, 63, of Halfway, Ore., was traveling southbound when he failed to negotiate a left curve and was ejected from his motorcycle. The man, who was wearing a helmet, ended up down a 30-foot embankment and into the Payette River.

He was pronounced dead at the scene.

Authorities also responded to motorcycle crash near the Idaho, Oregon border. They say Eric Shink, 40, of Kennewick, Wash., was headed eastbound on Interstate 84 when he struck a guard rail and was ejected from his motorcycle.

Shink, who was wearing a helmet, was pronounced dead at the scene. Alcohol and speed are believed to have been factors in the crash.

The third crash, Idaho State Police says, occurred about 18 miles from Stanley on Highway 75. Officials say an Idaho Transportation Department employee was doing routine maintenance on the highway when he saw two people and a motorcycle on the bank of the Salmon River.

Authorities say Ronald and Sharon Weber, of Boise were riding a motorcycle when for unknown reasons, they drifted off the right shoulder and down a 90-foot embankment. Both were pronounced dead at the scene. Alcohol is not believed to be a factor in the crash.