Honda announced it was forced to halt production at a vehicle plant in Japan after discovering its computer systems had been affected by the WannaCry ransomware attack, Reuters reported.

The automaker shut down operations at its Sayama plant Monday after finding the malware. The location generally produces around 1,000 vehicles per day, including the Accord sedan as well as the Odyssey and Stepwagon minivans. Operations continued at all other plants and resumed at Sayama Tuesday.

Read: NSA Hacking Tools Used In WannaCry Global Ransomware Attack Targeting Hospitals, Banks And Tech Companies

Honda first discovered the WannaCry virus on its computer systems Sunday. The company said the presence of the ransomware affected its networks across Japan, North America, Europe, China and other regions.

A spokesperson for Honda reported the company attempted to secure its systems in May when the WannaCry ransomware attack began hitting computer systems but was unable to successfully protect all of its network from the attack.

WannaCry began its spread last month, infecting hundreds of thousands of computer systems around the world in a matter of just days. The attack hit networks belonging to major corporations as well as hospitals and other organizations.

The attack made use of a Windows exploit first discovered by the U.S. National Security Agency. That exploit was stolen by a group of hackers known as the Shadow Brokers and made public. While the NSA tipped off Microsoft to the vulnerability and the company published a fix, most systems were not updated in time to protect against the attack.

Read: Microsoft MS17-010 Vulnerability: EternalRocks Attack Spreading Using Same Exploit As WannaCry Ransomware

The temporary closing of Honda’s plant is just the latest effect of the ransomware attack, and is evidence residual attacks are still happening even though the attack is largely over. It is believed similar attacks using other NSA exploits have also been launched and may put computer systems at risk.

Jonathan Penn, the director of strategy for cybersecurity firm Avast, told International Business Times his company has thus far observed 1.3 million encounters of WannaCry in 153 countries. He advised the best solution for companies who may be affected by WannaCry and similar attacks is to invest in proactive security.

Structure Security Newsweek is hosting a Structure Security event Sept. 26-27 in San Francisco. Photo: Newsweek Media Group

“Last month’s global WannaCry attack was — or at least should have been — a wake-up call that security should be proactive, not reactive,” Penn said. “Planning ahead is even more critical when business operations are at stake. Companies like Honda should be aware of the tools and resources available to them to secure their networks and ensure business continuity.”

Marco Cova, a senior security researcher at malware protection platform Lastline, told IBT the WannaCry infection at Honda shows cyberattacks are a concern for all types of businesses, not just “online” companies.

“Nowadays, every business is an online business and can be affected by a security incident, either as part of targeted attacks or as part of random malicious activity,” Cova said. “This incident also shows that security incidents have more and more frequently an impact in the physical world: Just like WannaCry affected the ability of the NHS to offer services to its patient, now we have an example of manufacturing capability being impacted by an attack.”