Chinese shipping giant COSCO fell victim to a ransomware attack this week, Bleeping Computer reports. The type of ransomware is unknown, but COSCO urged its employees not to open suspicious emails and requested that IT staff run antivirus on internal networks.

The attack targeted the company’s U.S. website and email systems. BBC reports that the cyberattack forced staff to forego internal systems and use Twitter and free Yahoo email addresses to handle customer queries. Company operations outside of the United States were not affected. However, a press release on the COSCO website yesterday said, “For safety precautions, we have shut down the connections with other regions for further investigations.”

This maritime industry attack does not compare in scope to last year’s NotPetya attack on Maersk, the world’s largest shipping firm. Maersk reportedly lost up to $300M as a result of the attack.

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