Editor's Note: This story has been updated to reflect a pending third first-degree murder charge in relation to the female victim's unborn child. 

A Jefferson County man who reported a voice told him to “kill the meth addicts” allegedly murdered a pregnant 31-year-old woman and her 2-year-old son on West Main Street in Jefferson City Monday afternoon after he became convinced the child’s baby stroller contained methamphetamine, according to authorities.

Detective Sgt. Roland Holt with the Jefferson City Police Department identified the deceased woman as Sierra Cahoon. The detective did not identify Cahoon’s 2-year-old son.

The man who was driving the car that struck Cahoon and her child, William David Phillips, 33, North Highway 92, Jefferson City, is charged with two counts of first-degree murder. A third count of first-degree murder is expected to be filed related to the death of the unborn child. 

This morning Phillips remained in the Jefferson County Jail without bond.

“This act was done with premeditation,” the arrest warrants state.

Holt also charged Phillips with attempted first-degree murder for allegedly intentionally striking a man named Tillman Gunter, who was walking on East Main Street.

Phillips was apparently driving extremely fast when he hit Cahoon and her son. His Chevrolet crashed through the wall of Sustainable Aquatics and came to rest about 10 feet inside the structure, according to business owner John Carberry, who said the mother and child were killed instantly.

“I don’t think they suffered,” he said. “I just want to let the police do their job and mourn the passing of this mother and child. It’s very sad.”

A Sustainable Aquatics employee was cut by glass as she left the building. She required three stitches on her thumb and on her leg, according to Carberry.

The car ruptured fish tanks containing thousands of gallons of water and killed about 2,000 fish, Carberry added.

Phillips and a male passenger in his car were not seriously injured in the 3:30 p.m. crash They both climbed out of the crashed car and fled. Phillips was detained by citizens until police arrived. The passenger apparently eluded authorities.

Before colliding with the aquatics store, Phillips struck a stop sign with sufficient force to snap the metal pole and send it over the two-storey business. It hit a vehicle approximately 300 feet away.

Gunter, who was struck by Phillips’ car on East Main Street, was transported to Jefferson Memorial Hospital.

“(Phillips) was driving down Main Street in Jefferson City looking for people to kill with his car when he saw the victim, Tillman Gunter, walking and he intentionally drove his car into him,” the attempted first-degree murder warrant states. “(Gunter) said he tried to get away from the car, but (Phillips) kept coming.”

Minutes before, Phillips was driving on Chucky Pike when he believed a voice told him to kill meth dealers, according to the first-degree murder warrants.

Investigators ordered a blood test on Phillips.