Senate unanimously voted through a call for new leadership, and some top military commanders were pressing for a coup. In response to this pressure, Thiệu made some changes to his cabinet, and Prime Minister Trần Thiện Khiêm resigned. This did little to reduce the opposition to Thiệu. On 8 April, a South Vietnamese pilot and communist, Nguyễn Thành Trung, bombed the Independence Palace and then flew to a PAVN-controlled airstrip; Thiệu was not hurt. Many in the American mission—Martin in particular—along with some key figures in Washington, believed that negotiations with the communists were still possible, especially if Saigon could stabilize the military situation. Ambassador Martin's hope was that North Vietnam's leaders would be willing to allow a "phased withdrawal" whereby a gradual departure might be achieved in order to allow helpful locals and all Americans to leave (along with full military withdrawal) over a period of months. Opinions were divided on whether any government headed by Thiệu could effect such a political solution. The foreign minister of the Provisional Revolutionary Government (PRG) had indicated, on 2 April, that the PRG might negotiate with a Saigon government that did not include Thiệu. Thus, even among Thiệu's supporters, pressure was growing for his ouster. President Thiệu resigned on 21 April. His remarks were particularly hard on the Americans, first for forcing South Vietnam to accede to the Paris Peace Accords, second for failing to support South Vietnam afterwards, and all the while asking South Vietnam "to do an impossible thing, like filling up the oceans with stones." The presidency was turned over to Vice President Trần Văn Hương. The view of the North Vietnamese government, broadcast by Radio Hanoi, was that the new regime was merely "another puppet regime." Last days All times given are Saigon time. PAVN encirclement On 27 April, Saigon was hit by PAVN rockets—the first in more than 40 months. With his overtures to the North rebuffed out of hand, Tran resigned on 28 April and was succeeded by General Duong Van Minh. Minh took over a regime that was by this time in a state of utter collapse. He had longstanding ties with the Communists, and it was hoped he could negotiate a ceasefire; however, Hanoi was in no mood to negotiate. On 28 April, PAVN forces fought their way into the outskirts of the city. At the Newport Bridge (), about five kilometres (three miles)