were the missionaries ever attacked during their mission?
Yes, on January 8, 1956 they were attacked and speared by a group of Huaorani warriors.
Operation Auca
Their efforts came to an end on January 8, 1956, when all five—Jim Elliot, Nate Saint, Ed McCully, Peter Fleming, and Roger Youderian—were attacked and speared by a group of Huaorani warriors. 
what is operation auca? An attempt by five Evangelical Christian missionaries to bring Christianity to the Huaorani people. where were these people from? US can you name the five missionaries? Jim Elliot, Nate Saint, Ed McCully, Peter Fleming, and Roger Youderian. can you tell me something more about the first person? born in Portland, Oregon, to Fred and Clara Elliot. Fred was of Scottish heritage; his grandparents were the first of his family to settle in North America. what about the second person? Born in 1923, when he was seven he took his first plane ride with his brother Sam, who would eventually become a commercial pilot for American Airlines. when did the missionaries first tried to contact the people? September 1955. what was the result of the meeting? By the end of the month, they had identified several clearings in the jungle. Elliot learned several phrases in the language of the Huaorani from Dayuma, a young Huaorani woman who had left her society and become friends with Rachel Saint, a missionary and the sister of Nate Saint. did anything happen at palm beach? Yes, on December 23, the Flemings, Saints, Elliots and McCullys together made plans to land at Palm Beach and build a camp on January 3, 1956. where is this place located? UNANSWERABLE
wiki:15820600
Operation Auca [SEP] Introduction
Their efforts came to an end on January 8, 1956, when all five—Jim Elliot, Nate Saint, Ed McCully, Peter Fleming, and Roger Youderian—were attacked and speared by a group of Huaorani warriors. The news of their deaths was broadcast around the world, and "Life" magazine covered the event with a photo essay. The deaths of the men galvanized the missionary effort in the United States, sparking an outpouring of funding for evangelization efforts around the world. Their work is still frequently remembered in evangelical publications, and in 2006 was the subject of the film production "End of the Spear". Several years after the death of the men, the widow of Jim Elliot, Elisabeth, and the sister of Nate Saint, Rachel, returned to Ecuador as missionaries with the Summer Institute of Linguistics (now SIL International) to live among the Huaorani.