WASHINGTON (CBSDC/AP) — A top State Department lawyer warns that the use of cyberattacks against the United States could be seen as an act of war.

Harold Koh, legal adviser for the State Department, made the comments Tuesday before the U.S. Cyber Command Inter-Agency Legal Conference.

“Cyber activities that proximately result in death, injury, or significant destruction would likely be viewed as a use of force,” Koh said.

Koh explained that cyber activities in certain situations break customary international law, which can trigger a nation to begin to act in self-defense.

“A State’s national right of self-defense, recognized in Article 51 of the UN Charter, may be triggered by computer network activities that amount to an armed attack or imminent threat thereof,” he said.

Cited examples of launching military action for a cyberattack include causing a nuclear plant meltdown, opening a damn that destroys a populated area or disabling air traffic control stations that result in deadly plane crashes.

“Only a moment’s reflection makes you realize that this is common sense: if the physical consequences of a cyberattack work the kind of physical damage that dropping a bomb or firing a missile would, that cyberattack should equally be considered a use of force,” Koh said.

Koh’s comments come as the U.S. continues to deal with cyberattacks from China.

“No diplomatic actions have made a difference,” Richard Bejtlich, chief security officer for Virginia-based cybersecurity firm Mandiant, told The Associated Press. “They remain aggressive — they’re kicked out one day and try to get back in the next day.”

Defense Secretary Leon Panetta, who is leaving China Thursday, told reporters that he spoke with Chinese officials to continue to have a dialogue with the U.S. about cyberattacks.

“I think it’s clear that they want to engage in a dialogue on this issue and I guess that’s the most important thing,” Panetta told the AP. “That’s the beginning of trying to perhaps be able to develop an approach to dealing with cyber issues that has some semblance of order here as opposed to having countries basically all flying in the dark.”

Senior intelligence officials have accused the Chinese of stealing high-tech data for economic gain.

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