16-year-old twins have been arrested for what police call the brutal murder of their mother in their Conyers, Georgia home.

A task force lead by Conyers Police arrested Tasmiyah and Jasmiyah Whitehead Friday morning after a four-month investigation.

One was arrested at Tucker High School, the other at a relative’s home in Clarkston.

“One was somewhat hostile and the other was, from what my detectives have told me, almost passive, almost disinterested,” Conyers Police Chief Gene Wilson said.

The sisters have been charged with murder and will be prosecuted as adults.

“I think that speaks about how vile this act was and just how vicious the overall attack was,” said Chief Wilson.

The Chief said Jarmecca Whitehead was found stabbed and beaten to death January 13 in her home.

The twins originally told police they found their mother when they came home from school.

There was a Rockdale County Sheriff Deputy in their Bridle Ridge Walk subdivision.

Chief Wilson said one of the girls flagged down the deputy.

Chief Wilson said the case was resolved when the Georgia Bureau of Investigation crime lab came back with conclusive evidence.

“As the investigation went on and the evidence was sent to the GBI to be processed, it pointed clearly to who was responsible for the murder,” Wilson said. However, he did not disclose what that evidence was.

“It was a brutal murder,” he said. “She was stabbed and beaten to death and as far as the motive, I just don’t know.”

Wilson said neither girl offered an apology when they were arrested.