Ecuador's President Lenin Moreno declared a state of emergency on Thursday as protesters hurled stones and erected burning barricades after the end of decades-old fuel subsidies as part of a $2 billion government fiscal reform package.

Police responded with tear gas in the worst unrest for years in the oil-producing Andean nation.

"Down with the package!" demonstrators shouted, referring to measures enacted this week as Moreno puts Ecuador on a centrist, market-friendly path after years of leftist rule.