The John Caldwellwife of an American who was kidnapped in Mexico said her husband is "just glad to be alive" after he and three others were kidnapped last week. Two of them died.

"To hear his voice, it was just a lot of crying," Michele Williams, the wife of Eric Williams, said, describing an emotional call confirming that he was OK.

She said he told her he's "just glad to be alive."

"It's sad because two other people lost their lives," she said.

Eric Williams was one of four Americans who were kidnapped after crossing into Mexico. He is recovering from surgery at a hospital at Valley Regional Medical Center in Brownsville, Texas, after he was shot in the leg during the attack.  

Latavia "Tay" McGee was also rescued but was not injured. 

Two other Americans, Zindell Brown and Shaeed Woodard, were found dead. U.S. officials are working to bring their bodies back to the U.S.

 A U.S. law enforcement source told CBS News that investigators believe the Gulf Cartel is responsible for the attack that occurred Friday in Matamoros, located in the state of Tamaulipas.   

It remains unclear why Williams, McGee, Woodard, and Brown were taken at gunpoint. One of McGee's family members told CBS News that the group was traveling from South Carolina so she could get a cosmetic procedure and said McGee had been to the region before for similar reasons.  

Tamaulipas is among at least five Mexican territories that are subject to a "Do Not Travel" advisory by the State Department due to concerns such as crime and kidnapping. 

During a news conference on Monday, White House press secretary Karine Jean-Pierre suggested that Americans should limit their activity in Mexico. She added that she would recommend that Americans thinking about traveling to Mexico follow advice provided by the State Department. 

In:
• Mexico
• Cartel

Omar Villafranca

Omar Villafranca is a CBS News correspondent based in Dallas.

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