PETALUMA (CBS SF) — A homeless man has been arrested in the brutal assault of a 7-Eleven clerk that was captured on an in-store security camera, authorities said Wednesday.

Dale Edward Ostrand (Sonoma County Sheriff’s Office)

Petaluma police said they received a call at 6:03 a.m. Tuesday to report a violent robbery at the 7-Eleven located at 430 Washington St.

Upon arrival, officers found a clerk who sustained significant head injuries and had no recollection of what occurred. Officers reviewed the store’s surveillance footage and established a violent battery and subsequent robbery.

The footage revealed the clerk was punched in the side of the head by a male suspect, who officers immediately recognized as Dale Ostrand. The punch was unprovoked and immediately rendered the clerk unconscious.

Investigators said Ostrand then left the store after taking merchandise without paying. The merchandise: a cup of coffee.

The clerk was eventually found on the floor by another employee coming to work.

Ostrand, who is a Petaluma transient with extensive law enforcement contacts, was located nearby after a search of the area and taken into custody without incident. He was booked into the Sonoma County Jail.