Ignacio Zaragoza, sent his gunboat "Veracruz" to shell the rebel forces behind the oil tanks. Mayo sent a letter to both parties stating he would remain neutral, but to protect American lives and property, he would "take all necessary steps." Mayo then evacuated several Americans, but refused to land troops to protect the American refinery. After additional rebel attacks on 7 and 8 April at the Iturbide Bridge, the foreign population sought refuge on the American ships, and the German cruiser "Dresden" and British cruiser "Hermione". Clarence Miller, American consul in Tampico, sent an urgent request for help in evacuating the American population within the city. Then, on the evening of 8 April, a marine courier for the American consulate was detained but soon released.