The latest in a series of massive demonstrations dubbed “the mother of all protests” erupted in Caracas and other Venezuelan cities Wednesday against the South American country’s increasingly unpopular president, Nicolas Maduro. At least three people were killed, according to human rights groups, bringing the death toll from recent protests to seven. Angry demonstrations have grown increasingly common as critics have accused the socialist Maduro of driving the country to ruin and demanding a timetable for elections the opposition believes it will win. Maduro has responded with heavy-handed moves to maintain his grip on power. Maduro said the crowds of hundreds of thousands were part of an effort to overthrow his government.