Venezuela’s opposition on Tuesday sought to harness anger over a massive blackout that deepened hardship nationwide, but turnout at a Caracas demonstration was relatively modest as many Venezuelans despair of an imminent solution to their plight.

Lights came back on in parts of the capital and other areas of Venezuela overnight following a nearly nine-hour outage that the government blamed on an “electromagnetic attack” against the power grid, without providing any evidence. Government opponents say years of mismanagement and corruption were to blame, according to AP.

Electricity supply remained unstable in many regions. The blackout knocked out communications and the Caracas metro on Monday, forcing commuters to walk home or hustle for a spot on packed buses. The metro remained out of operation Tuesday.