TOKYO - Tokyo Electric Power Company Holdings Inc. said Monday it will postpone until an unspecified date the restart of its nuclear reactor northwest of Tokyo -- its first since the 2011 Fukushima disaster -- due to a control-rod alarm failure.

The Kashiwazaki-Kariwa nuclear complex in Niigata Prefecture was initially set to restart on Tuesday, but an alarm designed to sound when two non-paired control rods are withdrawn from the reactor fuel core failed to trigger during a test Saturday, the utility said at a press conference.

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