Police in Philadelphia have identified a suspect in the assault of a Temple University professor Tuesday.
The attack happened around 11:20 a.m. as a man robbed the 81-year-old professor in his office at knife point.
Philadephia police have issued an arrest warrant for 45-year-old Darryl Moon, who was identified through video surveillance.
He's described as a 6 foot 2 inch tall black man, 280 pounds, with black hair and brown eyes.
Police said he has 16 prior charges, including multiple robberies, assaults and thefts.
Moon is considered armed and dangerous.
Anyone with information on Moon's whereabouts is asked to call Philadelphia Central Detectives Special Investigations Unit at 215-686-3047, 215-686-3048 or 215-686-3093.