When they continued to preach, Muhammad VII ordered them executed and had their bodies dragged through the streets. In addition to this proselytisation incident, raids and skirmishes were increasingly common on the frontiers. Both authorities found it difficult to prevent unauthorized raids, and once raids had been carried out it proved difficult to restore the peace without losing face. In one raid, some Granadans went as far as Cartagena on the Murcian coast. An even larger raid took place in 1405. On the eastern front, Muslim attacks against Vera and Lorca were repulsed, but the invaders captured Ayamonte, a Castilian castle on Granada's western border. Henry III sent an emissary, Gutierre Diaz, to the Granadan court to protest. Meanwhile, Granada, Aragon, Castile and Navarre (a small Christian kingdom in the north of the peninsula) were engaged in diplomatic communications. In 1404 Granada and Aragon conducted talks in Barcelona. At the same time, Henry III proposed a meeting at Logroño with Martín I of Aragon and Charles III of Navarre to build an anti-Granadan coalition. However, Charles III of Navarre decided to help Granada instead. His kingdom was small, like Granada, and he was worried about the growth of Castilian power. Navarre traditionally had a good relationship with its Muslim minorities, which may have influenced Charles' diplomatic posture. Charles III wrote to "my brother" Muhammad VII telling him of the upcoming Logroño summit against Granada and promising to keep him informed of the outcome. He also sent three ships loaded with wheat, as well as 300 siege machines to help Granada against a potential invasion. Granada-Navarre communications were impeded by their geographical separation—Navarre was in the north of the peninsula while Granada was in the south, and Castilian territories lay between them. A Navarrese ambassador, travelling to Granada via Castile disguised as a merchant, was intercepted by Alfonso Fernández of Aguilar in Alcala de Real. This put an end to Granada-Navarre communications and caused Henry III to cancel the Logroño meeting. Meanwhile, Martin I of Aragon, focused on his problems in Sicily and Sardinia, was also uninterested in a war against Granada. Instead, Muhammad VII and Martin I agreed to a treaty of friendship on 4May 1405. The treaty allowed commerce and prisoner exchanges between the two states. In addition, Muhammad VII would supply Aragon with 400–500 knights and pay their cost of between 2,840 and 3,540 "doblas" per month.