Demonstrators, led by mining groups and rural unions, have clashed with law enforcement in Bolivia as tensions simmer over the country’s economic crisis, the worst in decades.On Thursday, small explosions were heard in the midst of the protest in La Paz, credited to miners setting off small sticks of dynamite. Some protesters were reported as attempting to breach the presidential palace.The unrest follows weeks of road blockades, as miners, farmers, teachers and rural workers express frustration over the country’s ongoing economic turmoil.Bolivia used to be a major exporter of natural gas, but in recent years, its reserves began to shrivel,…