their archive to indicate this. In 1933, France occupied Andorra as a result of social unrest before elections. On 12 July 1934 an adventurer named Boris Skossyreff issued a proclamation in Urgel, declaring himself Boris I, sovereign prince of Andorra, simultaneously declaring war on the Bishop of Urgell. He was arrested by Spanish authorities on 20 July and ultimately expelled from Spain. From 1936 to 1940, a French detachment was garrisoned in Andorra to prevent encroachment as a result of the Spanish Civil War and Francoist Spain. During World War II, Andorra remained neutral and was an important smuggling route from Spain into France. The French Resistance used Andorra as part of their route to get downed airmen out of France. In 1943, Andorra carried out its first execution since the 19th century: Antoni Arenis was executed for double fratricide by firing squad because a trained executioner was unavailable to operate the legal method, by garrote. Long an impoverished land with little contact with any nations other than adjoining France and Spain, Andorra, after World War II, achieved considerable prosperity through a developing tourist industry. That development, abetted by improvements in transport and communications, has tended to break down Andorra's isolation and to bring Andorrans into the mainstream of European history. Public demands for democratic reforms led to the extension of the franchise to women in the 1970s and to the creation of new and more fully autonomous organs of government in the early 1980s. Since the 1990s Andorra formally became a parliamentary democracy in May 1993 following approval of a new constitution by a popular referendum in March 1993. The new constitution retained the French and Spanish co-princes although with reduced and narrowly defined powers. Civil rights were greatly expanded, including the legalisation of political parties and the provision for an independent judiciary. Andorra joined a customs union with the European Communities (now the European Union) in 1991 and was admitted to the United Nations on 28 July 1993. It became a member of the Council of Europe in 1994. The country has been seeking ways to improve its export potential and increase its economic ties with its European neighbours. The financial services sector of the economy is highly important because of Andorra's status as a tax haven and its banking secrecy laws. See also List of Co-Princes of Andorra History of Europe History of Catalonia History of France