According to the San Mateo County Sheriff's Office, Greenberg allegedly stabbed a man because he was riding his bike on the sidewalk.

The victim suffered multiple stab wounds by the time police arrived at around 6:40 p.m. and arrested Greenberg.

The San Mateo County Sheriff's Office said it found a four-inch folding knife at the scene, which they believe was the weapon used in the attack.

Greenberg has been charged with assault with a deadly weapon.