CARACAS, Venezuela -- The lights are flickering back to life across much of Venezuela following a massive blackout.

Energy Minister Freddy Brito said Tuesday that power has been restored in the capital of Caracas and at least five of the South American nation's 23 states. Partial power has returned to another four states.

The outage hit shortly after 4 p.m. on Monday, halting the Caracas metro and snarling traffic at rush hour.

Officials blame an "electromagnetic attack" against the nation's hydroelectric system, while government opponents say years of mismanagement and corruption leave the grid vulnerable to failure.

It follows an outage in March that left millions of Venezuelans without water or phone communication for nearly a week.