Lorenza Marrujo is 67 years old and less than five feet tall — but she's no weakling.

An intruder recently confronted Marrujo at her seniors apartment complex in Fontana, California. Not only did she protect herself, but her neighbors, too.

"As he was coming towards me, I said, 'back off.' Right away," Marrujo said.

Marrujo has 26 years of martial arts training, so when she told the intruder to back off, he listened. Unfortunately, he made his way to the apartment of 81-year-old Elizabeth McCray — Marrujo's neighbor.

"He grabbed me and shook me, and I went down on the floor," McCray said.