Officials from the US government are warning of another wave of cyberattacks primarily targeting American corporations, reports the New York Times. Unlike the statements concerning Chinese cyber-espionage issued by the Pentagon in its recent report to Congress, these attacks are purportedly an effort to sabotage, officials say.

The sources are yet unknown, but are believed to originate from somewhere in the Middle East. Furthermore, it isn’t known whether the cyberattacks are state-sponsored, or the work of hackers or criminals. The attacks have mainly targeted energy companies and have thus far appeared to be probes searching for vulnerabilities that would grant access to processing systems.

“We are concerned by these intrusions, and we are trying to make sure they don’t lead to something much bigger, as they did in the Saudi case,” said an unnamed senior official to the New York Times. He was referring to the attack on Saudi Aramco, one of the world’s largest oil producers, in 2012, which affected 30,000 computers. The hackers in that incident claimed they attacked the company in retribution for its “oppressive measures” in the Middle East.

These new attacks are reminiscent of the Saudi case, and are unusual when compared to the string of cases that have been in the news lately, because they seek to cause damage rather than steal intellectual property. In that regard they are akin to the Stuxnet/Flame worm used by the United States and Israel to target and disrupt Iran’s nuclear enrichment plants.

The US government decided to release the warning once it became clear how deeply the attackers had managed to penetrate the affected systems. According to one official, one of the systems that was compromised is used to manage chemical processes.