Two senior cybersecurity officials say that the world should brace itself for more physically destructive hacks, warning that a more dangerous era is already upon us.

Paul Chichester, the director of operations at Britain's new National Cyber Security Center, said electronic intrusions would become more "destructive, disruptive and coercive."

"That will be our future," he told a crowd of officers, academics and industry experts gathered in London for a symposium hosted by the Royal United Services Institute, a venerable defense think tank.

Air Force Lt. Gen. James K. McLaughlin, deputy commander at U.S. Cyber Command, told attendees that infrastructure-wrecking attacks were being seen "right now in the environment."

"Three years ago these were just theoretical," he said Wednesday. "Now we see them. They're practically here in front of us."