Sen. Chuck Schumer warns that an attack last year on a California power plant proves that terrorists could take down whole stretches of the U.S. power grid.

But the New York Democrat said on Sunday that power companies now have the right to veto proposed security requirements.

The senator is calling for the federal energy regulator and the Department of Homeland Security to draft tougher new security standards overseen by Congress that would end the industry’s veto rights. Schumer has written a letter to both agencies requesting officials to consider such a change.

Last April, multiple snipers shot down 17 transformers at a Silicon Valley plant, firing outside security perimeters. The attack nearly brought down power to all of Silicon Valley. The perpetrators are still at large.

(AP)