PLYMOUTH, Mass. (AP) _ A device that was lowering a nuclear fuel bundle into a pool of water at the Pilgrim plant accidentally dropped its load Wednesday, but no damage was detected, plant officials said.

A refueling process that was about two-thirds complete was halted, said Anita Flanagan, spokeswoman for Boston Edison, the plant operator.

Flanagan said there was no immediate sign of damage to the fuel assembly, and plant workers did not detect any increases in radiation.

Boston Edison reported the incident to the Nuclear Regulatory Commission even though the utility was not required to do so, said Karl Abraham, an NRC spokesman. Abraham said the malfunction was not considered a serious incident. The plant has been shut down since May 4 to replace fuel in the reactor. Originally, utility officials hoped to restart the plant in mid-July.

Flanagan said the refueling would remain on hold until operators fully determine what caused the malfunction and correct it.