Morehead City, N.C. — Hazardous materials crews finished cleaning up a spill of explosive materials at the state port in Morehead City Thursday afternoon, allowing the port to reopen.

Nine 50-kilogram drums filled with the explosive PETN were punctured by a forklift early Tuesday as they were being unloaded at the port. Officials said Wednesday that they had found PETN leaking from drums in shipping containers not involved in Tuesday's accident.

Also known as pentaerythritol tetranitrate, colorless PETN crystals are the primary ingredient in detonating cords used for industrial explosions. The compound also is used in military devices and blasting caps, as well as in heart medications.

PETN was used in an attempted Christmas Day bombing of a Detroit-bound Northwest Airlines flight, and it was used by Richard Reid, the notorious "shoe bomber," who tried to blow up a jet in 2001.

The PETN was shipped to Morehead City from Spain, and a private contractor brought it into the port, according to Lt. Robert Jones of the State Ports Authority Police.

The Coast Guard oversaw the cleanup and the investigation into the spill, and officials announced after 5 p.m. Thursday that the port had been reopened.

During the almost-three-day closure, the State Ports Authority worked with customers to meet their needs by moving cargo from the port to customer facilities and allowing ships to dock.

The state port handled 1.9 million tons of cargo in the fiscal year that ended last June, including 118 shiploads and 415 barges.