During opening arguments Tuesday outside St. Petersburg, prosecutors said 45-year-old Ronald Earl Williams somehow activated his cell phone, which then called his wife's cell phone.
The phone's voicemail recorded Williams saying he was going to kill her and prosecutors say it recorded 31-year-old Mariama Williams' terrified screams immediately after.
Prosecutors are seeking a first-degree murder conviction and the death penalty on the grounds that the crime was heinous, atrocious and cruel.
Williams' attorney is arguing the killing was not premeditated.
Information from: St. Petersburg Times, http://tampabay.com