Hartleys First News Today

>> reporter: on falcon lake there has been no sign of david hartleys body, his jet ski, anything that could prove his wifes story, that her husband was shot to death by mexican drug smugglers. the beheading of the one mexican detective, willing to at least try to solve the crime, has dealt the hartleys another blow. you feel right now theres people in mexico, maybe even police in mexico, who wont say what happened to david. >> yes. >> reporter: because theyre afraid. >> yes. if you have threats ...

>> only people with jet skis are involved with dope. >> right. >> reporter: clearly nervous, colette barely slowed down as we approach the church tiffany and david hartley visited on september 30th. he turned the boat and gave us 30 seconds to take the pictures at the exact spot tiffany hartley said they had stopped. >> this is the last place they came to, the old guerrero church. they took pictures on the front step, according to tiffany hartley. and they set down this channel to head back, and...

Wandered into a drug war and were mistaken as the enemy. >> reporter: zapata county sheriff siggy gonzalez believes the hartleys not only wandered into a war but had arrived on the mexican side of falcon lake at the exact moment a cartel was about to move a large amount of marijuana. up on a bluff, the spotters, his sources told him, caught the first glimpse of a possible glitch in the drug deal. >> that area is an area thats notorious for crossing or storing of thousands of pounds of marijuana....

Reynosa, jut south of mcallen. he was a district manager for an oil company. >> it was a blessing to us and our marriage. yeah. we were -- thats where we truly grew as a couple and had adventures. >> reporter: when the hartleys first arrived here this peaceful town was a perfect place for the young couple to live, but slowly it became more and more violent. there is a war in reynosa. two drug cartels battling for turf. the zetas, a rogue band of former military, are trying to push out the gulf c...

♪ ♪ >> reporter: on falcon lake there has been no sign of david hartleys body, his jet ski, anything that could prove his wifes story, that her husband was shot to death by mexican drug smugglers. the beheading of the one mexican detective, willing to at least try to solve the crime, has dealt the hartleys another blow. you feel right now theres people in mexico, maybe even police in mexico, who wont say what happened to david. >> yes. >> reporter: because theyre afraid. >> yes. if you have ...

>> reporter: without any clear answers from mexico, the hartleys have turned to intelligence sources north of the border who can try to explain why the couple was targeted. former intelligence official fred burton has been studying a turf war in mexico between two drug cartels. a former band of military guards called the zetas and the more traditional gulf coast cartel. >> what most people dont realize when youre looking at the border is that there are certain portions that are not controlled by...

>> reporter: david hartley had always been interested in visiting the sunken church in falcon lake. on thursday morning, september 30th, 2010, a week before he and his wife would move home to colorado, david decided they would go. >> did you know then what you must know now, that there had been several attacks on that lake? that fishermen dont cross into mexico on that lake anymore. >> we did know there were attacks. we didnt know where exactly. >> reporter: you had no worries whatsoever when yo...

Straddling the u.s.-mexican border two hours north of mcallen. >> weve had along the border, shootings. weve had along the border, murders, home invasions, burglaries, rapes. all types of crime where its associated with what i call spillover violence. >> reporter: siggy gonzalez was the sheriff in zapata, texas, and oversaw the investigation of the hartley incident. he has retired since our interview. >> i remember when i started as a deputy sheriff back in the 1970s, where this was used for dru...

Seen surrounding the case. >> the most likely scenario is, david and tiffany hartley had wandered into a drug war and were mistaken as the enemy. >> reporter: zapata county sheriff siggy gonzalez believes the hartleys not only wandered into a war but had arrived on the mexican side of falcon lake at the exact moment a cartel was about to move a large amount of marijuana. up on a bluff, the spotters, his sources told him, caught the first glimpse of a possible glitch in the drug deal. >> that are...

>> only people with jet skis are involved with dope. >> right. >> reporter: clearly nervous, colette barely slowed down as we approach the church tiffany and david hartley visited on september 30th. he turned the boat and gave us 30 seconds to take the pictures at the exact spot tiffany hartley said they had stopped. >> this is the last place they came to at the old guerrero church. they took pictures on the front step, according to tiffany hartley. and they set down this channel to head back, a...