SHIRLEY: People killed in the crash of TWA Flight 800 have been memorialised at a service marking the 20th anniversary of the disaster.

Family members of the 230 victims gathered with those who tried to rescue their loved ones on a Long Island beach on Sunday.

After the ceremony, family members dropped roses and white carnations into the ocean. Some wiped tears as they rubbed their hands over names on a memorial wall.

The midair explosion of Flight 800 moments after the flight left Kennedy Airport spawned a yearlong FBI probe and initially was thought to have been downed by a bomb or missile.

The National Transportation Safety Board eventually concluded that the probable cause was faulty wiring sparking an explosion of overheated vapours in the plane's centre fuel tank.