Sam Davis, the husband of an American missionary killed in Mexico, has said he will continue their work in that country.

Nancy Davis died last month after gunmen opened fire on the couple's truck about 70 miles south of the Texas border. The two were visiting churches they helped establish in Mexico.

Davis said despite the dangers he will continue to visit and support the churches in there.       

"I miss her terribly, but those people who killed her need to be saved," Davis told the Associated Press. "I pray for them, that God will have mercy on them and help them to know him."

He added that those who killed his wife will likely never be caught and tried.

"I am not angry with God that my wife is gone," Davis said. "I don't understand why he took her. But I know that he has a plan that is working out and it's part of that plan. And so, I remain committed and surrender to his will even though my heart is hurting and I'm grieving."