Steelmaker Nucor Shuts Down Some Output After Cyberattack (1)

Nucor Corp., the biggest steel manufacturer in North America, shut down production at some of its facilities after detecting an unauthorized intrusion into its computer systems.

The company took potentially affected systems offline and implemented other containment measures, Nucor said in a disclosure filed with the Securities and Exchange Commission on Wednesday.

Nucor said it is investigating the incident with external cybersecurity experts and has notified federal law enforcement. It is currently in the process of restarting the affected operations, according to the statement.

A company spokesperson did not immediately respond to a request for comment.

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