Officials shut down a North Carolina port and a stretch of highway and urged people to leave the area Tuesday after a forklift operator punctured at least one container filled with a powerful explosive.
The material was pentaerythritol tetranitrate, but it's not clear what form it was in, Mayor Jerry Jones said.
The chemical is also known as PETN, the substance authorities say was part of a device a Nigerian man used to try to bring down a Detroit-bound Northwest flight on Christmas Day. PETN is often used in military explosives and found inside blasting caps. It is also the primary ingredient in detonating cords used for industrial explosions.
Jones said the damage appeared to be an accident and there were no concerns about terrorism. He said a dock worker punctured a container as he was unloading barrels of the chemical.
There were no injuries.
Any accident involving hazardous materials must be reported immediately to the Morehead City Fire Department.
"That's how we found out about it," Jones said. "We don't think there's a danger. Everything is under control. But you have to be careful."
Officials had earlier said nine containers were punctured, but Jones said he was not sure exactly how many were damaged.
As a precaution, authorities closed a roughly 10-mile stretch of Highway 70 and a bridge and blocked off about 10 streets in the vicinity, the Cateret County News-Times reported.
Jones said he did not know the chemical was being shipped through the port, but whoever was shipping it should have contacted the city's emergency management department.
A telephone message left for Morehead City Fire Chief Wes Lail was not immediately returned.
Karen Fox, a spokeswoman with the North Carolina State Ports Authority, said the chemical was being unloaded in Morehead City. But she said she did not know where the shipment came from or where it was headed.
"Explosive materials are handled routinely at the port," she said.
Meanwhile, police told people near the port to stay away from windows and doors. Officers were sent downtown to knock on doors and relay alert and evacuation recommendations. About 8,800 people live in the coastal town.
Morehead City police spokeswoman Amy H. Thompson said people close to the port were leaving, but she did not know how many.
The Morehead port is one of the deepest on the East coast. Its Web site says its top import last year was sulfur products and the top export was phosphate.
Locals said there was no sense of panic. Drew Hall, who answered the phone at Crystal Coast Jamboree, a concert hall near the port, said she could see police lights.
"Everybody is going about their business," said Hall, 27 who has lived in Morehead City her whole life and does not remember a similar incident. "Why get nervous? Things happen. You can't freak out in times like this. If you freak out, you're going to go down."