Helen Washington told her grandson over and over to stop putting his cup of tea on her furniture. After he kept doing it anyway, the 75-year-old shot him, Hennepin County prosecutors allege.

When police arrived, the victim was waiting for them in the front yard of the residence in the 5800 block of N. Camden Avenue in Brooklyn Center on Oct. 12 with a gunshot wound to the right thigh, a criminal complaint said. He told officers his grandmother had shot him during an argument over where he had placed the cup, it said.

Washington, 75, now faces charges of second-degree assault with a dangerous weapon, a felony.

The victim's age and name weren't disclosed in the filing.

Prosecutors said officers spoke with a minor at the scene who told them that Washington had gotten upset with her grandson after he ignored her demands to keep his cup off the furniture. After dumping the tea out, Washington got up and left the room, apparently to fetch a gun, prosecutors said. When she returned, she resumed arguing with her grandson, who had poured a new cup of tea and again placed it on the furniture, the minor reportedly told police. As the argument continued, Washington pulled out the gun and shot her grandson in the leg, according to prosecutors.

Officers found a .38 Special revolver with five rounds of ammunition, one of which had been fired, prosecutors said. Washington was arrested at the scene, telling officers that she didn't think she should go to jail and asking them where she had hit her grandson, the complaint said.

A judge this week ordered Washington to be evaluated to see whether she is competent to stand trial. She is next scheduled to appear in court on Dec. 18.

A message for her court-appointed attorney wasn't immediately returned on Wednesday afternoon.

Libor Jany • 612-673-4064 Twitter:@StribJany