BERLIN (AP) — German conglomerate ThyssenKrupp says it suffered a "massive" and sustained cyberattack aimed at stealing industrial secrets.

The company said Thursday it was "a professional attack which according to our information can be attributed to a group in Southeast Asia."

ThyssenKrupp says the attackers targeted its Industrial Solutions unit and some data appeared to have been stolen.

The Essen-based company says that particularly sensitive departments, such as its naval and power plant units, are specially protected and weren't affected by the attack.

German weekly WirtschaftsWoche reported that the attack lasted six months before it was successfully fought off.

Last month Deutsche Telekom suffered a large-scale outage after its network was attacked by a so-called botnet comprised of millions of hijacked internet-connected devices, including fridges, televisions and heating systems.