(NBC) -- A manhunt was underway Monday for an inmate who escaped from a Detroit courthouse by stabbing a sheriff's deputy with a makeshift shank, stealing his uniform and carjacking a minivan, authorities said.
"He is armed and dangerous," Detroit Police Chief James Craig said of the suspect, identified by NBC station WDIV as Derrick White.
The deputy, who was unarmed and working alone, was putting three inmates in a holding cell at the Frank Murphy Hall of Justice and had just uncuffed White, 25, when he pulled a homemade weapon.
"After he stabbed the deputy he took the deputy's clothing, he took his keys, he got on the prisoner elevator and he escaped from the building."
Once outside, he stole a 2000 gray Dodge Voyager from a civilian but eventually ditched it, police said.
White was described as a 5-foot-6 black male, weighing about 155 lbs, last seen wearing a white T-shirt and gray pants. He was believed to be in northeast Detroit.
Napoleon said the escape was well-planned.
"He obviously paid very close attention to how the process works," the sheriff said.
He said courthouse metal detectors would not have picked up the plastic comb. Fortunately, it broke while the inmate was stabbing the deputy, he said.
The unidentified deputy had several puncture wounds to the neck but was not seriously injured, officials said. He was able to call for help using a courthouse phone.
The courthouse was put on lockdown after the 8:30 a.m. escape but has since reopened.
Napoleon said officials will review procedures but it does not appear the deputy broke any rules.
"It's a process that occurs thousands of times a year," he said.