Washington: The U.S. military’s Cyber Command hunted down foreign adversaries overseas ahead of this year’s mid-term elections, taking down their infrastructure before they could strike, the head of U.S. Cyber Command said.

U.S. Army General Paul Nakasone said the cyber effort to secure the vote began before the Nov. 8 vote and carried through until the elections were certified.

“We did conduct operations persistently to make sure that our foreign adversaries couldn’t utilize infrastructure to impact us,” Nakasone, who is also the director of the U.S. National Security Agency, told reporters.

“We understood how foreign adversaries utilize infrastructure throughout the world, we had that mapped pretty well, and we wanted to make sure that we took it down at key times.”

Nakasone’s language suggests Cyber Command carried out both offensive and defensive cyber operations.

He declined to identify which adversaries were targeted but acknowledged he saw the same kinds of foreign adversaries as he had in the past.

“I saw the same foreign adversaries that I’ve seen before, a lot of the same ones, the proxies and the elements of the Russian and Iranian governments that do this type of work,” Nakasone said.

The United States has given high priority to cyber operations to safeguard major elections in recent years, particularly since U.S. intelligence agencies accused Russia of trying to sway 2016 elections, a charge Moscow has denied. U.S. agencies also accused Iran of trying to influence American elections, which Tehran has denied.

Nakasone says the campaign to safeguard the latest U.S. elections fit into his broader campaign of persistent engagement, which includes operating overseas with partners to observe adversaries’ cyber tradecraft and malware on foreign networks.

“This is the idea of understanding your foreign adversaries and operating outside the United States,” he said.

He said the goal was to expose those adversaries, working with foreign governments hosting his teams and with the private sector.

“I am trying to make it as costly (as possible) for our adversaries to operate in terms of their time, money, and focus,” he said. (Reporting by Phil Stewart; Editing by Lisa Shumaker)