An argument over religion in Tennessee turned violent when a woman smacked a man on the back of his head and he responded by shooting her with a shotgun, authorities say.

Calvin Johnson, Sr., 69, has been charged with the first-degree murder of a woman “tentatively identified” as 45-year-old Tamara Perkins, according to an arrest affidavit reviewed by Law&Crime.

The violence unfolded on Tuesday.

Johnson, Perkins, and a third person were drinking at a home on the 3100 block of Morningside Street in Memphis, the affidavit says. At some point, an argument broke out when “Perkins and Johnson began to argue over religion,” police wrote, citing the third party.

The witness told police Perkins “poured a drink over Johnson’s head and slapped Johnson on the back of the head,” the affidavit says. The situation had escalated, but it would not stop there.

Johnson is said to have “entered his bedroom for a short time and returned with a shotgun, then, without a word and seemingly unprovoked, shot Perkins,” according to the affidavit. Perkins had not had a weapon on her, nor were any threats exchanged, the witness told police.

A Memphis police officer arrived at the home to find Perkins unresponsive “with a gunshot wound to the upper left abdomen lying next to a double barrel shotgun inside the residence,” the affidavit states. Johnson was observed “on top of the victim,” and when the officer asked him what happened, he is said to have replied, “I shot her,” police wrote.

Perkins was brought to a nearby hospital where she died. Johnson was arrested.

When homicide detectives interviewed Johnson back at their bureau, he allegedly uttered several phrases unprompted, such as “I killed her” and “I’m in trouble, ain’t I?”

The suspect is also said to have uttered, “I messed up, didn’t I?” and when told of his Miranda rights, refused to answer questions, allegedly asserting instead, “She came at me and she a big woman.”

Court records show Johnson has a bail hearing on Monday and then must report to court again on Thursday.