The National Cyber Authority (NCA) said on Wednesday that civil defense authorities have blocked a massive cyber attack on Israeli businesses and infrastructure in recent days.

The Authority said in a press release that there have been recent indications of a large-scale attempted strike on the Israeli economy. The statement said the attacker posed online as a legitimate organization that sends emails in the name of the organization while simultaneously trying to attack about 210 other organizations, government ministries, public bodies, and private individuals. At the same time, the attacker falsified “security certificates” in the name of these companies.

In response to the attack, the NCA said it will publish instructions for individuals, businesses, and government offices to protect themselves against technology attacks. In addition, the NCA is taking further action to include publishing recommendations for the private sector which will be available on the NCA’s home page.