HARRISBURG, Pa. (AP) – A fire broke out in a transformer next to a decommissioned reactor at Three Mile Island nuclear power plant Wednesday, an Exelon Nuclear official said.

The official, David Simon, said crews were still trying to figure out the cause of the fire, but that there was no danger to the public and no interruption in the plant’s operations. There were no reports of injuries.

“At no point was there any danger to the public,” said David Sanko, head of the Pennsylvania Emergency Management Agency. The fire was reported to the Emergency Management Agency at 11:06 a.m. and was out about 20 minutes later, agency spokeswoman Maria Smith said.

The decommissioned reactor, known as Unit 2, is owned by First Energy Corp. and was the site of the nation’s worst commercial nuclear accident, when a portion of the reactor’s core melted in 1979.

Unit 1 is operated by Exelon and owned by a joint venture involving Exelon and British Energy.