Five line-of-duty deaths in 2010 have shaken the California Highway Patrol and again raised awareness of the hazards faced by officers issuing citations alongside highways with fast-moving vehicles.

Three of the officer deaths have occurred in the past week.

Two of the officers were killed Sunday in separate incidents.At 3:38 a.m., Officer Justin McGrory was conducting a traffic stop on a vehicle, northbound Interstate 15 in San Bernardino County. For unknown reasons, a vehicle veered off the roadway and struck the officer while he stood on the right side of his cruiser. His partner provided medical aid.

At about 6:30 p.m. on Sunday, Officer Brett Oswald responded to a report of a collision in San Luis Obispo County. The officer had called for a tow truck and was waiting next to his patrol vehicle when a passing vehicle crossed over the double yellow lines and struck him.

Officer Philip Ortiz succumbed June 22 to injuries he sustained June 9, while conducting an enforcement stop on the right shoulder of northbound I-405 (San Diego) Freeway in West Los Angeles. Ortiz was struck from behind by a vehicle being driven on the right shoulder of the freeway.

This year, the CHP has also lost Officer Tom Coleman in a June 11 motorcycle accident and Officer Daniel Benavides in a fixed-wing airplane crash.