The New York Times is reporting that China’s People’s Liberation Army has resumed its attacks against Western targets after a three-month hiatus. Shanghai-based Unit 61398 is back in business, says the Times, albeit using different techniques.

Past attacks have sought intellectual property and government documents, including blueprints, manufacturing plans, pricing documents, and other proprietary information, mostly from U.S. companies. More recently, however, the group has been aiming at companies with access to the nation’s power grid. Earlier this month, the Pentagon released a report identifying the Chinese military as the source of years of attacks.

Meanwhile, three political leaders are calling for a hardened grid. Rep. Trent Franks (R-Ariz.), Rep. Yvette Clarke (D-N.Y.) and the Hon. James Arbuthnot of Great Britain are co-chairs of the Electric Infrastructure Security Summit. They wrote a commentary for Politico about the value of a partnership to promote a strong smart grid. “New questions are being raised about the electric grid’s vulnerability,” they wrote. “If we don’t change our course, national electric grids could be headed for disaster. And our societies cannot survive without them.”

The three admitted that hardening the grid will take time and that “finding an optimum mix of corporate, legislative and regulatory initiatives won’t be easy.”