Costa Rica hosts many refugees, mainly from Colombia and Nicaragua. As a result of that and illegal immigration, an estimated 10–15% (400,000–600,000) of the Costa Rican population is made up of Nicaraguans. Some Nicaraguans migrate for seasonal work opportunities and then return to their country. Costa Rica took in many refugees from a range of other Latin American countries fleeing civil wars and dictatorships during the 1970s and 1980s, notably from Chile and Argentina, as well as people from El Salvador who fled from guerrillas and government death squads.