Gudarostea), with 100,000 soldiers, was made up of battalions of different ideologies. It was well armed but poorly trained, and one of its most acute deficiencies was the absence of heavy artillery and an air force. Aguirre begged Indalecio Prieto and Manuel Azaña to send some aircraft. Historians agree that it was not a viable option because of the difficulties in breaking the Siege of Biscay. However, 40 to 50 airplanes were sent in different shipments, most flying over enemy territory. Others were sent across France and, after being disarmed, were retained or returned to Barcelona or Valencia in accordance with a "no intervention" policy. Another factor that contributed decisively to the Basque Army's defeat was its lack of a qualified general staff. In June 1937, the Nationalists broke through the Iron Ring of Bilbao and entered the city as a result of the treachery of Alejandro Goicoechea, the engineer who had designed the fortifications. Aguirre moved his government to Trucíos before he headed to Santander and finally to Catalonia, where he prepared to continue fighting with his men. In May, Aguirre had entered into talks with the Italians, through intermediaries, about a possible surrender. The talks continued, with the leader of the Basque Nationalist Party, Juan de Ajuriaguerra, discussing terms, the Santoña Agreement, to allow a withdrawal from Bilbao if Nationalist troops did not attack the city. However, they attacked, and Aguirre refused to sign the surrender agreement and fought on. Exile Aguirre fled the country after the war and was pursued for years by agents of Francisco Franco. His exile took him to Paris, Berlin and New York City. In June 1940, the Breton Yann Fouéré gave him documents that allowed him to escape France, which had been invaded by the Wehrmacht. Aguirre fled first to France, where he organised camps and services for Basque refugees and the government-in-exile. Caught behind enemy lines, he was in Belgium when Hitler occupied that country. He then fled to Berlin, where he lived underground until a false identity was arranged. Under the protection of a Panaman ambassador (Germán Guardia, who provided him with a Panamanian passport), Aguirre reached Sweden. Dodging SS German intelligence, he arrived in Rio de Janeiro on the ship Vasaholm on 27 August 1941. The Brazilian customs authorities registered a Panamanian, Dr. José Álvarez Lastra, and a Venezuelan, María de Arrigorriaga, accompanied by their children, José and Gloria.