Authorities worked Wednesday to determine the damage caused by a fire and possible explosion at the Maine Yankee nuclear power plant, while officials warned the reactor could be off-line for "several months."

The fire broke out Monday night in the non-nuclear side of the plant, Maine Yankee officials said. There were no reports of injuries, and officials with the federal Nuclear Regulatory Commission said there was no danger of radiation being released and no threat to the public.The fire apparently started in the area near the main transformer, which feeds electricity produced by the plant to the transmission system outside the plant, officials said.

The cause of the blaze was not immediately known, but it may have started within the electrical wiring systems leading from the generator to the transformer, or possibly within the generator itself, officials said.

Plant officials and NRC inspectors were still trying to determine what sparked the blaze, and whether the "loud noise" reported by several people was an explosion.

"The cause of it is still under investigation," said Maine Yankee spokesman Marshall Murphy.

Officials were also trying to assess the damage to the plant's main generator, saying that was the key to determining how low long the reactor remains out of service.