(MONTERREY, Mexico) -- A dedicated Texas missionary couple strangled in their Mexico home knew how much danger they were in, but refused to leave the people they cared for, according to a friend from their sponsor church in Texas.
"They had opportunities to return, but these are their people. It would be like abandoning family. We don't abandon family," Karen Mosley, the secretary for Liberty Baptist Church in Lewisville, Texas, told ABC News. "We lost a couple of great prayer warriors."
John Casias, 76, and Wanda Casias, 67, were found dead at their home near Monterrey, Mexico, on Tuesday by one of their 10 children. They had been living and working in Mexico for about 30 years.
It was the second time in a year that an American missionary was killed in Mexico. Nancy Davis, 59, was shot in the head in January 2011 when she and her husband were attacked at an illegal road block.
"They had all kinds of updated security measures, which makes us all believe it was somebody he knew or he wouldn't have let them in," Mosley said. She said they lived on a walled property and had a gate.
Mosley said church members used to go on missions every other year to the area where the Casias couple lived, until about four years ago when things became too dangerous for them to travel there. Fighting between drug cartels over the past few years made Monterrey an extremely dangerous place.
"John doesn't allow visitors to come to his place anymore. It's that bad," Mosley said. "There are no more policemen, they're all dead. The last mayor was murdered. All they have there are soldiers."
The couple had discussed what they wanted, should anything ever happen to them, with members of the church, Mosley said. The couple said that if they were to be kidnapped, they did not want anyone to pay ransom for them.
"They would not allow it," Mosley said. "They knew it was dangerous. They were just cautious and they made a pact."
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