(CNN) -- Two U.S. Border Patrol agents who were assisting in the apprehension of suspected illegal immigrants were killed Thursday when their vehicle was struck by a train, officials said. They were driving an unmarked Border Patrol vehicle when it was struck by a 90-car freight train at a crossing about nine miles west of Gila Bend, Arizona, the agency said. Authorities were investigating what caused the accident that killed Border Patrol Agents Eduardo Rojas Jr. and Hector Clark, Homeland Security Secretary Janet Napolitano said in a statement. The vehicle, an SUV, was struck by the train at the rail crossing of Paloma Road near exit 106 of Interstate 8. "This is unfortunate not just for me, not just for the Yuma Sector, but for the Border Patrol as a whole," Border Patrol spokesman Kenneth Quillin said. The agents were on duty and were assisting other officers in tracking down a group of people suspected to have entered the country illegally, Quillin said. The agents were trying to position themselves north of where the other agents were, he said. Both Clark, 39, and Rojas, 35, were lead agents in the Border Patrol's Yuma Sector, the agency said. Rojas, who had been working with the patrol for more than 11 years, is survived by his wife and two children. Clark, who had been working with the patrol for nearly 10 years, also is survived by his wife and two children. "This tragedy is a reminder to all of us that whether they are facing down a criminal suspect with a weapon, or patrolling the highways and deserts, these law enforcement professionals encounter life-threatening dangers every day," Arizona Attorney General Tom Horne said. Napolitano noted the service of others as she expressed sympathy for the victims and their families. "We also keep in our thoughts and prayers all of those who put their lives at risk every day, at home and abroad, to defend our country. We honor their service and pray for their continued safety," she said. On Friday, a Mexican man was arraigned in a U.S. federal court for the killing last December of Border Patrol Agent Brian Terry in Arizona. CNN's Mike Ahlers contributed to this report.
NEW: The Border Patrol says the agents' vehicle was struck by a 90-car freight train .
NEW: Both agents had been working with the Border Patrol for about a decade .
Homeland Security Secretary Janet Napolitano says authorities are investigating .
The agents were assisting in the apprehension of suspected illegal immigrants .
(CNN) -- Two U.S. Border Patrol agents who were assisting in the apprehension of suspected illegal immigrants were killed Thursday when their vehicle was struck by a train, officials said. They were driving an unmarked Border Patrol vehicle when it was struck by a 90-car freight train at a crossing about nine miles west of Gila Bend, Arizona, the agency said. Authorities were investigating what caused the accident that killed Border Patrol Agents Eduardo Rojas Jr. and Hector Clark, Homeland Security Secretary Janet Napolitano said in a statement. The vehicle, an SUV, was struck by the train at the rail crossing of Paloma Road near exit 106 of Interstate 8. "This is unfortunate not just for me, not just for the Yuma Sector, but for the Border Patrol as a whole," Border Patrol spokesman Kenneth Quillin said. The agents were on duty and were assisting other officers in tracking down a group of people suspected to have entered the country illegally, Quillin said. The agents were trying to position themselves north of where the other agents were, he said. Both Clark, 39, and Rojas, 35, were lead agents in the Border Patrol's Yuma Sector, the agency said. Rojas, who had been working with the patrol for more than 11 years, is survived by his wife and two children. Clark, who had been working with the patrol for nearly 10 years, also is survived by his wife and two children. "This tragedy is a reminder to all of us that whether they are facing down a criminal suspect with a weapon, or patrolling the highways and deserts, these law enforcement professionals encounter life-threatening dangers every day," Arizona Attorney General Tom Horne said. Napolitano noted the service of others as she expressed sympathy for the victims and their families. "We also keep in our thoughts and prayers all of those who put their lives at risk every day, at home and abroad, to defend our country. We honor their service and pray for their continued safety," she said. On Friday, a Mexican man was arraigned in a U.S. federal court for the killing last December of Border Patrol Agent Brian Terry in Arizona. CNN's Mike Ahlers contributed to this report.
assisting in the apprehension of suspected illegal immigrants were killed Thursday when vehicle when it was struck by a 90-car freight Hector Clark, Homeland Security Secretary Janet for the Yuma Sector, but for the Border Patrol as said. The agents were on duty and were assisting agency said. Rojas, who had been working with the