(CNN) - The flag-draped cases of 18 Americans killed in Afghanistan arrived at Dover Air Force Base in Delaware early Thursday, in a solemn event attended by President Obama.
Also in attendance for the transfer of the bodies were U.S. Attorney General Eric Holder and Michele Leonhart, acting DEA administrator.
The bodies were of three Drug Enforcement Administration special agents and 15 U.S. troops who died in Afghanistan this week.
The DEA agents were killed Monday as they returned from a raid on a compound believed to be harboring insurgents tied to drug trafficking. Their helicopter with seven troops aboard went down in western Afghanistan.