As many as 350 buildings, including private homes and small businesses, may have been damaged by the fire at the N.P. Johnsens fireworks factory in Kolding in western Denmark, 125 miles west of the capital, Copenhagen.
The blaze was thought to have started Wednesday when two containers of fireworks were being loaded onto a truck, police said. It quickly spread to a nearby building and led to a chain reaction of explosions.
One of the explosions was the equivalent of a magnitude-2 earthquake, according to the Geological Survey of Denmark and Greenland.
It was unclear what caused the container to combust.
About 2,000 people living near the factory were evacuated as authorities set up a security perimeter. It might take days before people can return, police spokeswoman Gitte Schou said as firefighters worked to cool the containers.
Although the plant has a license to store 330 tons of fireworks, as much as 2,200 tons was stockpiled, police said.
A 33-year-old firefighter was killed and 17 people, including firemen, rescue workers and police officers were treated for minor burns and smoke inhalation, Schou said. Overnight, about 60 people were under medical observation after complaining about respiratory problems.
