MEDFORD, MA — The teenager who police said stabbed a Chinese food delivery driver in the back last weekend was arrested. Nicholas Davis, 18, was arrested Saturday morning on charges of armed robbery and assault and battery with a dangerous weapon (knife.)

Police said Davis came up behind the delivery driver and stabbed him before taking some money from his hand while the victim lay on the ground.

Liang Cheng, 42, an employee of Café May, underwent six hours of surgery and had his kidney and gallbladder removed, the restaurant's former owner told the Medford Transcript.

