Sheriff: Fla. pre-med student confesses to stabbing mother to death

April 7 (UPI) -- A 21-year-old University of Florida student has been charged with first-degree murder after allegedly confessing to stabbing his mother to death at her Florida home over the weekend, authorities say.

Emmanuel Espinoza drove to his mother's home in Frostproof to attend a family event on Saturday and confronted his mother, 46-year-old Elvia Espinoza, when she opened the front door, Polk County Sheriff Grady Judd said in a video posted to social media.

At that point, Judd said, the pre-med student "began to stab her and he stabbed her many times. She ran from him. She was talking to a family member on the phone. And in addition to that he stabbed her until she fell down and died."

Emmanuel Espinoza was arrested and charged with first-degree murder after calling police and confessing to the crime, the sheriff said. He called it a "truly horrible situation."

Elvia Espinoza was a second grade teacher at Ben Hill Griffin Elementary School in Frostproof, located about 65 miles south of Orlando.

Judd said the victim's son told authorities he had wanted to kill his mother "for many years because she got on my nerves."