A 13-year-old California boy is being hailed as a hero after he stopped a man from kidnapping his 4-year-old sister.

According to authorities, a man approached the siblings while they were playing on their lawn, grabbed the young girl and began walking away.

Her quick-thinking brother grabbed her arm and began screaming for help.

The girl was not hurt in the incident. The kidnapper was arrested nearby and is being held on $100,000 bail.

Sergeant Eric Metten with the Los Angeles County Sheriff's Department said of the brave 13-year-old, "He was very responsible for his family and obviously his loved one, his 4-year-old sister."

"He's our hero for today."

Watch the clip above.