The female victim was hospitalized in critical but stable condition. She was in surgery Tuesday afternoon.
Riverside Police responded to a report of the robbery/assault at about 12:30 p.m. Tuesday on the 1700 block of University Avenue.
Officers found a female employee locked inside the business. She was bleeding from a head wound. Officers had to forcibly enter the business as the woman had locked herself inside after the attack.
A UPS driver called 911 minutes after the attack.
Investigators determined a male suspect walked into the business before 12:30 p.m. and walked around inside. He then went behind the counter and struck the clerk with a heavy, blunt object believed to be a mallet-style hammer repeatedly on the head. The woman lost consciousness.
The suspect then opened cash registers and removed money. He took various other items and left, striking the victim on the back of the head on the way out.
The suspect was described as an African-American man in his late 30s/early 40s, standing about 6 feet tall and weighing about 210-230 pounds. He has thick brushy hair with a receding hairline.
The suspect was caught on surveillance tape during the robbery and assault.
Anyone with information related to the case should contact Riverside Police Detective Rick Wheeler at (951) 353-7134 or Detective Rick Cobb at (951) 353-7135.