The truck was found near the Lake Bridge on Business 377 in Granbury.
Investigators believe the remains are those of Helen Hollady who disappeared in September 1979.
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.
"The first thing we were thinking was, 'We've been looking for Miss Holladay for years.'"
Sheriff Deeds said the front and rear of the pick-up truck were sticking out of the water.
"When we pulled the vehicle out, we found the skeletal remains of a person and also found identifying information with the body to tie it to Miss Holladay," said Deeds.
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.
Read more: http://www.nbcdfw.com/news/local/Remains-Found-Inside-Truck-in-Lake-Granbury-Solves-Cold-Case---255820631.html
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