JINAN - Four people died and six others were slightly injured in a refrigerated warehouse fire in east China's Shandong Province, authorities said Thursday.

The fire occurred at around 10:40 a.m. Thursday when workers were dismantling an old refrigerated compartment of a foreign trade foodstuff firm in Anqiu City, the city government said.

One person died at the scene and three died in the hospital. The six people who were injured have been hospitalized.

The fire was put out at mid day.

An initial investigation result showed the blaze was caused when thermal insulation materials were ignited as workers were welding pipes, the government said.