The badly decomposed body of Alicia Fox, 27, was discovered in a vacant Detroit house on Monday night with two gunshot wounds to the head.
Fox's husband, Erin Justice, was arrested in the Atlanta area Wednesday and Detroit homicide investigators have flown to Georgia to speak with him, Detroit Police Chief James Craig told reporters.
"We believe that he has information that can lead us to the children ... but we're not certain," Craig said. "We are hopeful the children are alive. That's our hope and our prayer that the children are alive."
Police dug in the backyard of the home on Detroit's northwest side that Fox had shared with Justice, their 8-month-old son Kristian Justice and Fox's daughter, Kaylah Hunter. Kaylah has a different father. Police said investigators stopped digging Wednesday night and are now hoping that tips from the public will help them find the siblings.
Justice initially wasn't reported as a person of interest or a suspect in his wife's slaying, but authorities now want to charge him in her killing, Craig said. The Wayne County prosecutor's office was reviewing the request for a murder charge, spokeswoman Maria Miller said.
Justice flew to Atlanta several days ago and had been scheduled to fly back to Detroit. He was interviewed Tuesday by FBI agents in Atlanta.
"I have no idea why he was in Atlanta," Craig said, adding that he didn't know when the man would be returned to Michigan.
Wayne County Circuit Court records show Justice pleaded guilty to carrying a concealed weapon in 2008 and was sentenced to probation.
Fox's relatives have told authorities that they last saw the mother and her children on May 24. People living next door to Fox said that was about the time they saw a U-Haul truck outside Fox's home.
Relatives searching for Fox received a tip and found her severely decomposed body in the basement of the vacant house about six miles from her home and called police.
Craig said blood was found at Fox's home.
A 27-year-old man will be charged as an accessory after Fox's death, Craig said.
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