Oct. 6, 2010 -- Mexican authorities have launched a search using boats and helicopters for the body of an American who was allegedly killed by Mexican pirates on a lake bordering the two countries.
The Mexican promise of help in the search for the body of David Hartley came after Mexican law enforcement officials cast doubt on the story by Hartley's wife that he was killed by gunmen on the Mexican side of Falcon Lake which lies between the two countries.
It also came after Texas Gov. Rick Perry asked Mexican President Filipe Calderon to call him with assurances that Mexican authorities are searching for Hartley's body.
Perry said that he hopes to hear from Calderon "within the next 48 hours, that the body has been retrieved. If not, we're not looking hard enough."
The Mexican Foreign Relations Ministry today said the country "is committed to the investigation of those acts." It added that Mexican authorities have "stepped up their actions with the support of specialized personnel, boats and helicopters."
Hartley's widow Tiffany defended herself earlier today on "Good Morning America" against Mexican law enforcement officials who suggested they doubted her story that her husband was shot dead while they on Jet Skis on the Mexican side of the lake. Mexican police said there is no evidence of a crime as described by Tiffany Hartley.
"It's hard just to hear it," she told "Good Morning America." "But I can see it from their point of view. I can understand why they might think that, but it's not true. ... I would never even think about hurting my husband.
"I loved him," she said.
Hartley told police the pirates shot her husband in the head. The 30-year-old man's body has not been recovered.
U.S. officials said they're prohibited from entering Mexican waters to search for his body.
David Hartley's mother, Pam Hartley, has issued a public plea to Secretary of State Hillary Clinton, asking for aid in bringing her son's body home.
"He needs to come home and we're begging the Mexican government, the governor of Texas, President Obama," the man's mother, Pam Hartley, told "Good Morning America" Tuesday.
"To Hillary -- mother to mother -- help me bring my son home, please," she said, crying. "She's a mother, she would know."
Dennis Hartley has said Mexican police aren't doing enough to find his son's body. On Tuesday he told The Associated Press that he believed the Mexican authorities were being paid off by drug cartels.
Couple Disregarded Warnings About Danger
David Hartley was a history buff. Tiffany Hartley, 29, said she and her husband dismissed warnings about crossing into the Mexican side of the lake so they could take pictures of a historic church. She said it had been some months since they had heard reports of pirates being on the lake.
While they were making their way back to the U.S. border, they were approached by three boats of fully armed pirates, she said.
"David and I were racing back to the U.S., and they started shooting," she told "Good Morning America." I looked back, and I saw that David had been shot, and I turned around to go get him."
Under Attacks, Woman Had to Leave Injured Husband Behind
Hartley said she tried as hard as she could to pull her husband onto her own Jet Ski to take him to safety, "but he's a lot bigger than me.
"You can't imagine how awful it was not being able to help him," she said.
Knowing her own life was in jeopardy, Hartley said she was forced to abandon her husband. She took her Jet Ski at top speed back to the U.S. shore and placed a panicked 911 call.
U.S. authorities have searched Falcon Lake on the American side, to no avail.
The state of Texas had warned boaters and fisherman as long ago as April to stay away from the Mexican side of the lake. Since then, the drug wars along the border have gotten more violent and there have been reports of more pirate encounters.
Lake Has Become Pirate's Haven
Falcon Lake, part of the Rio Grande situated directly on the Texas-Mexico border, has recently become a haven for the pirates, and there have been at least five reported run-ins with pirates on the lake so far this year, although this is the first reported case of a death.
"The one thing I dreaded on Falcon Lake has happened," Texas' Zapata County Sheriff Sigifredo Gonzalez said. "The lake is not secure, the border is not secure because the incident that I dreaded the most has, in fact, happened. We cannot go to Mexico, we cannot recover that body, we cannot conduct an investigation, we have to tell the family we can't do anything about it."
The Associated Press as well as ABC News' Kevin Dolak and Sarah Netter contributed to this report.