WEST PALM BEACH, Fla. – A Florida teenager has been sentenced to 18 months in juvenile detention for coaxing his senile grandmother into holding a gun and threatening to shoot “all the pigs” in a homemade “gangster rap” video.

Eighteen-year-old Michael Alfinez pleaded guilty Tuesday to elder abuse charges. His family has said the case was a misunderstanding.

The 85-year-old grandmother can be seen in the video holding a handgun, wearing a black mask and threatening to shoot “all the pigs.”

Alfinez was arrested in April after authorities seized the tape during a routine traffic stop. Alfinez and others also could be seen in the video shooting a pistol around town.

Alfinez also pleaded guilty to charges of firing out of a moving vehicle and into a building.