Battle of Saigon ( 1955 ) The Battle for Saigon was a month - long battle between the Vietnamese National Army of the State of Vietnam ( later to become the Army of the Republic of Vietnam ) and the private army of the Binh Xuyen organised crime syndicate . At the time , the Binh Xuyen was licensed with controlling the national police by Emperor Bảo Đại , and Prime Minister Ngo Dinh Diem issued an ultimatum for them to surrender and come under state control . The battle started on April 27 , 1955 and the VNA had largely crushed the Binh Xuyen within a week . Fighting was mostly concentrated in the inner city Chinese business district of Cholon . The densely crowded area saw some 500 - 1000 deaths and up to 20 , 000 civilians made homeless in the cross - fire . In the end , the Binh Xuyen were decisively defeated , their army disbanded and their vice operations collapsed . Prelude . On the midnight of 29 – 30 March , explosions rocked Saigon as the Binh Xuyen responded to Diem ' s removal of its police chief . 200 Binh Xuyen troops launched an attack on VNA headquarters . The clashes were inconclusive , with the VNA suffering six deaths to their opponents ' 10 , but by sunrise , the bodies of civilians littered the sidewalk . Battle . The final battle between Diem ' s VNA and the Binh Xuyen began on April 27 at mid - day . After initial small arms fire and mortar exchanges , the VNA resorted to the heaviest artillery in its arsenal . This coincided with growing calls from within the Eisenhower administration to oust him because Eisenhower believed that he was unable to subdue the Binh Xuyen and unify the country . By evening , a large part of the inner city was engulfed with street to street fighting . By the morning of April 28 , multiple explosions and house to house combat had driven thousands of civilians onto the streets . A square mile of the city , around the densely populated inner city Chinese district of Cholon where the Binh Xuyen had a stronghold , became a free fire zone . Artillery and mortars levelled the poor districts of the city , killing five hundred civilians and leaving twenty thousand homeless . Observers described that fighting from both sides as lacking strategy and relying on brute force attrition tactics . One of the few manoeuvres that were considered tactical was an attempt by the VNA to cut off Binh Xuyen reinforcements by demolishing the bridge across the Saigon - Cholon canal . This was made moot when the Binh Xuyen threw pontoon bridges across the canal . It appeared that the conflict would be determined by the side which was able to absorb the greater number of losses . Approximately 300 combatants were killed in the first day of fighting . On the morning of April 28 , John Foster Dulles , the US Secretary of State phoned J . Lawton Collins to suspend moves aimed at replacing Diem . Eisenhower had determined that these were to be put on hold pending the outcome of the VNA operation . Collins and Dulles clashed in the National Security Council meeting , with Collins vehemently calling for Diem to be removed . Collins continued to argue that the attempt to destroy the Binh Xuyen by force would produce a civil war . The NSC endorsed Dulles ' position . Aftermath . After 48 hours of combat , the VNA began to gain the upper hand . " Le Grande Monde " , previously Bay Vien ' s largest gambling establishment , and temporarily serving as a Binh Xuyen citadel , was overrun by Diem ' s paratroopers after a struggle which caused heavy losses on both sides . The VNA then stormed one of the Binh Xuyen ' s most heavily fortified strongholds , the Petrus Ky High School in Cholon . By the time Collins had arrived back in South Vietnam on May 2 , the battle was almost won . The Binh Xuyen forces were broken and in retreat and their command posts were levelled . Bay Vien ' s headquarters was battered and his tigers , pythons and crocodiles inside had been killed by mortar attacks and shelling . Bay Vien escaped to Paris to live out his life on the profits of his criminal ventures , and the VNA pursued the Binh Xuyen remnants into the Mekong Delta near the Cambodian border . Jubilant crowds gathered outside Diem ' s residence shouting " Da Dao Bao Dai " ( meaning " Down with Bao Dai " ) .