A global cyber attack identified as Petya ransomware targeted India’s largest container port, Jawaharlal Nehru Port Trust, on Wednesday forcing it to shut operations in one of its three terminals, PTI reported. Several companies and government institutions across the globe also fell prey to the attack that began in Ukraine. The United States, Europe, Russia and several countries in Asia were targeted in the attack.

The terminal, operated by AP Moller-Maersk, was unable to conduct loading and unloading operations because of the breach, Union Shipping Ministry Spokesperson Neeta Prasad said. Experts believe the ransomware, which demands $300 per computer in cyrptocurrency to free the systems from the breach, used a tool known as “Eternal Blue”, Bloomberg reported. The same hacking tool was used during the WannaCry attack in May.

Ukraine’s state power distributor, Kiev’s main airport, the National Bank of Ukraine and other firms were the first to report the cyber attack. Chernobyl nuclear plant workers had to resort to manually monitor radiation levels after its computers were targeted.

“With there being no global kill switch for this one, we will continue to see the numbers rise in different parts of the world as more vulnerable systems become more exposed,” Beau Woods, deputy director of the Cyber Statecraft Initiative at the Atlantic Council in Washington told Bloomberg.

In the United States, pharmaceutical company Merck said it had launched an investigation after its network was compromised, The Washington Post reported.

The WannaCry ransomware virus is a malicious software that had crippled systems worldwide and affected more than 150 countries in a cyber attack in May. It had locked data on computers it struck, which could only be released after a paying a ransom in bitcoins. The major cyber attack had targeted several nations, bringing operations at hospitals, telecommunications firms and other companies to a halt.