The National Memorial Day parade in Washington was to include a special recognition for first responders to the 9/11 attacks and to victims' relatives. Actor Gary Sinise and Medal of Honor recipients from the Korean and Vietnam wars were among the guests.
President Barack Obama was participating in a wreath-laying ceremony at the Tomb of the Unknowns at Arlington National Cemetery.
Meanwhile, U.S. troops fighting in Afghanistan paused to remember the fallen in Memorial Day services. Some prayed and held flag-raising ceremonies.