BROKEN ARROW, Oklahoma - Mike Roblyer and his friends are retired and spend their days working on classic cars.

For years, they rented their auto shop space from Ken Nix and they all became close friends.

"We just kind of, over the last three or four years, became pretty good friends, and we always help each other out," said Mike Roblyer.

Roblyer says he called Nix on Monday but never heard back and he remembers thinking that was odd so he got worried.

Police say Nix’s ex-wife, Judith, shot him in the head earlier that day.

She didn't call 911 until 9:30 p.m. Monday night and the call went out as a suicide.

When detectives arrived on the scene, they say the evidence and the woman's story did not match up.

They determined it wasn't a suicide at all. It was a homicide.

"Not sure if this was a pre-meditated type of situation or something happened earlier in the day that led to an argument,” said Caption Leon Calhoun of the Broken Arrow Police Dept. “That's still under investigation.”

Calhoun says officers have been to the home before, three different times for domestic-related calls.

And Roblyer says Nix talked about troubles at home, too. But nothing prepared him for the loss of his friend.

Police say Judith told her two daughters about the murder, but they never went to authorities. 

They arrested one daughter, Michele Davis-Pearson, for accessory after the fact and they're still looking for the other daughter.