Steelmaker Nucor said on Wednesday that it had experienced a cybersecurity incident and temporarily shut down some of its production operations as a precaution. The North Carolina-based company said it discovered "unauthorized third party access to certain information technology systems" that it uses.Nucor did not specify which production operations had been "temporarily and proactively" shut down in a regulatory filing but said it was currently working on getting them back up and running.  Its facilities a ...