Walker County Sheriff Clint McRae released the video as police searched for Adriana, a 13-year-old who was last seen Saturday in the Houston suburb of Katy, and investigated the death of her father, whose burned body was found more than 60 miles north of Katy on Sunday.
The video shows a Ford F-150 driving through the shot until it is parked just off camera. Then there appears to be a small explosion as a man runs away. In another video that McRae released, the man jogs down a nearby alley and into a parking lot.
That truck was discovered just off Interstate 45 in the Houston suburb of Conroe, which is south of the rural property in northern Walker County where the body of Adriana's father, Caesar Vladimir Coronado, was found Sunday.
McRae told reporters that investigators think speaking to the man in the videos will be "crucial in solving this case."
He also said there is an ongoing search in the Houston area for Adriana.
The director of the Texas EquuSearch Mounted Search and Recovery Team, Tim Miller, said the search area was 100 square miles in three counties north of Houston.
"We are driving (around), doing recon work, and picking out places that need to be searched," Miller said.
An Amber Alert was issued for Adriana on Monday
after investigators determined that she was missing and might have been with her father when he died. She is 5 feet tall and weighs about 105 pounds. She has brown eyes and wears black-framed glasses.
McRae said there has been no demand of ransom and none of the many tips as to her location has panned out.
He said investigators need to find and interview the man in the video. Finding him could be difficult given the darkness of the video (it was taken around 10:20 p.m.) and the fact that there is no clear shot of the man's face.
"It's going to take an individual who is familiar with and knows this potential suspect" to identify him through his manner of walking, his clothing and his profile, McRae said. Authorities believe the man is Hispanic, he added.
There is no obvious motive in the case, McRae told reporters.