David Hartley Update: Four suspects identified in Falcon Lake border shooting

(CBS/KGBT) HARLINGEN, Texas - Authorities in Zapata County, Texas have announced that they have identified four suspects in the Falcon Lake border shooting that claimed the life of David Hartley in September, and they confirmed that they were all known members of Mexico's Zeta drug cartel, according to local reports.

PICTURES: Tiffany and David Hartley

Zapata County Sheriff Sigifredo Gonzalez told CBS affiliate KGBT that Hartley's wife, Tiffany was a target that day but she was able to get away.

"They were watching her with a rifle to her body and they lowered it and pick it up and lowered," Gonzales told the station. "They were waiting for word whether to shoot her or not shoot her."

Their intent was to kill her," he said. "She was able to get away from them."

Gonzales also said that while interest in the case may have wavered since it made national headlines after the shooting five months ago, Zapata County hasn't stopped investigating, and won't stop now until the four suspects are in custody.

"Other than what we're doing locally, we don't know of any other agency, state or federal agency, doing anything else," he added. "It's just my office that's been doing anything about it."

The suspects are known to live in Mexico, according to Gonzales, but he said that since the attacks they have crossed into the U.S. several times. Gonzales says his investigators will continue to gather information until they have enough to arrest the men responsible.

Gonzales also told CBS' "The Early Show" that he believes the four identified suspects are part of a larger group of individuals responsible for the tragedy that day on Falcon Lake, saying, "I believe there were about seven or eight shooters."

The Sheriff's Office is also warning other boaters about the dangers lurking on the Mexican side of the lake, and will be posting signs nearly three times the size of their current ones asking them to avoid crossing over.

They have also set up metal posts in the middle of the lake to mark the border between the two countries.

Click here for complete coverage of Falcon Lake shooting on Crimesider