SANTIAGO — Thousands of protesters armed with stones, sticks and Molotov cocktails clashed with police on Sunday as Latin America"s biggest music festival opened, in the latest spurt of a four-month old wave of grassroots anger over economic inequality and other grievances. Police blocked the entrance to a park where the festival was being held in Vina del Mar, a seaside resort about 120 km (75 miles) west of Santiago. Officers used a helicopter and a balloon with surveillance cameras and drove back the protesters with water cannon and tear gas. "Vandals and criminals are trying to do damage just four blocks from the entrance to the festival. But everything is under control," Jorge Martinez, the Valparaiso regional governor, told the 24-hour state news channel. After failing to get into the festival grounds, protesters attacked nearby shops and the renowned O"Higgins Hotel where many festival artists usually stay. Tear gas drifting through the hotel forced many guests to flee. The protesters also burned at least seven vehicles. Despite the official optimism, the festival"s traditional Hollywood-style red carpet opening, one of Chile"s most watched televised events, was canceled. The crowd was able to enter three and a half hours before the start of the show after filing through two security fences erected in at least four blocks around the park. Multiple Grammy-winner Ricky Martin opened the show. After a two-hour set, he asked Chileans not to remain silent and to demand what they deserve with "love and peace." "That (Chileans) express themselves, that they demand the basics, human rights, is basic, we don"t ask for anything. I am with you Chile, never silent, always with love and peace," said the 48-year-old Puerto Rican singer. Hours earlier, at a press conference, Martin said it was "important to let the leaders of our countries know what we need, provided we do so in an orderly manner." At the height of the protests, the singer addressed a message to Chile"s President Sebastian Pinera on social media: "You have to know that the will of a people is respected, is obeyed, is fulfilled. Listen to your people." Since authorities announced a modest hike in metro fares in the capital Santiago on Oct. 18, more than 30 people have died in protests which mushroomed in an outlet for wider discontent over social and economic inequality and rejection of conservative billionaire Pinera and his government. A nationwide referendum on changing the constitution, which dates back to the era of military dictator Augusto Pinochet in the 70s and 80s, is set for April. — AFP