(AP) -- A memorial service is being held at Arlington National Cemetery for three soldiers whose helicopter was shot down in Laos in 1968.

Army Staff Sgt. Melvin Dye of Carleton, Mich., had been listed as missing in action for more than 40 years. Then in 2009, military officials told members of his family that they had excavated the crash site and had evidence Dye was killed.

Army Staff Sgt. Robert S. Griffith, of Hapeville, Ga., and Sgt. 1st Class Douglas J. Glover, of Cortland, N.Y., also were on board the helicopter. All three are to be honored at Arlington Tuesday.

Dye's sister, now 81, had held out hope her brother was still alive because there wasn't any conclusive DNA evidence of Dye found at the crash site.

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