The Hood County Sheriff's Office says investigators have positively identified the skeletal remains found in a submerged pickup in Lake Granbury, Texas, last week.
Investigators say dental records confirm the remains belong to Helen Holladay, a woman who disappeared 35 years ago in September 1979.
The sheriff's office says the VIN from the truck found near the Lake Bridge on Business 377 in Granbury also belongs to Holladay.
According to Sheriff Roger Deeds, a city employee first spotted the truck partially submerged in the lake as they were driving near the bridge on Pearl Street and called police.
Deeds said old police reports said there was some disturbance at the weekend home of Holladay in the Whippoorwill Bay subdivision north of the lake.
The disturbance was between Holladay and her husband Herman. Herman Holladay was a suspect when Helen was reported missing, according to police. He died in the 1980s.
Two surviving daughters were informed about the discovery, the sheriff said.
Detectives continue to work the case, but because of the deteriorated condition of the remains, her cause of death may never be known.
NBC 5's Scott Gordon contributed to this report.