Zion Baptist Church was being used as a fortress and armory. Purportedly twenty caskets full of rifles had been delivered to the church, though no evidence was found. Attack by air Numerous eyewitnesses described airplanes carrying white assailants, who fired rifles and dropped firebombs on buildings, homes, and fleeing families. The privately owned aircraft had been dispatched from the nearby Curtiss-Southwest Field outside Tulsa. Law enforcement officials later said that the planes were to provide reconnaissance and protect against a "Negro uprising". Law enforcement personnel were thought to be aboard at least some flights. Eyewitness accounts, such as testimony from the survivors during Commission hearings and a manuscript by eyewitness and attorney Buck Colbert Franklin, discovered in 2015, said that on the morning of June 1, at least "a dozen or more" planes circled the neighborhood and dropped "burning turpentine balls" on an office building, a hotel, a filling station, and multiple other buildings. Men also fired rifles at Black residents, gunning them down in the street. Richard S. Warner concluded in his submission to The Oklahoma Commission that contrary to later reports by claimed eyewitnesses of seeing explosions, there was no reliable evidence to support such attacks. Warner noted that while a number of newspapers targeted at Black readers heavily reported the use of nitroglycerin, turpentine, and rifles from the planes, many cited anonymous sources or second-hand accounts. Beryl Ford, one of the pre-eminent historians of the disaster, concluded from his large collection of photographs that there was no evidence of any building damaged by explosions. Danney Goble commended Warner on his efforts and supported his conclusions. State representative Don Ross (born in Tulsa in 1941), however, dissented from the evidence presented in the report concluding that bombs were in fact dropped from planes during the violence. In 2015, a previously unknown written eyewitness account of the events of May 31, 1921, was discovered and subsequently obtained by the Smithsonian National Museum of African American History and Culture. The 10-page typewritten letter was authored by Buck Colbert Franklin, noted Oklahoma attorney and father of John Hope Franklin. Notable quotes include: Franklin reports seeing multiple machine guns firing at night and hearing "thousands and thousands of guns" being fired simultaneously from all directions. He states that he was arrested by "a thousand boys, it seemed,...firing their guns every step they took." Arrival of National Guard troops Adjutant General Charles Barrett