Kabul, Afghanistan (CNN) -- Fourteen Americans died in two helicopter crashes in Afghanistan on Monday, NATO's International Security Assistance Force said: 10 in one incident and four in the other. Three Drug Enforcement Administration special agents were among the dead, according to the DEA, which did not identify them. The agents were first DEA agents to be killed in Afghanistan. "Like all those who give their lives in service to America, they were doing their duty, and they were doing this nation proud," President Obama said at the Naval Air Station in Jacksonville, Florida. "Now, it is our duty, as a nation, to keep their memory alive in our hearts and to carry on their work, to take care of their families, to keep our country safe," Obama said.
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Helicopter crash victims "gave their lives ... to protect ours," president says
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Three DEA personnel are among victims
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Seven U.S. service members and three U.S. civilians killed in one crash
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Four other U.S. service members killed when two copters collided Monday
"@placeholder is an extremely tight family, and the death of these three brave agents is a devastating loss for us," she said in a written statement.