Night of the Long Knives
Starting in the evening of 30 June 1934, the Night of the Long Knives, the Nazi purge, personally led by Adolf Hitler of internal political opponents, primarily Ernst Roehm and the SA. Others killed by Schutzstaffel (SS) and its Sicherheitsdienst (SD) intelligence service, or Gestapo personnel included people variously considered political risks or embarrassments to Hitler. Some of the other Nazi leadership, such as Hermann Goering, Joseph Goebbels, and Heinrich Himmler put their opponents on the list.
Shirer wrote that while the full story will probably never be known, key documents about both the Reichstag Fire and the Night of the Long Knives having been destroyed by Goering, "all the evidence that ha come to light indicates that the SA chief never plotted to put Hitler out of the way."Hitler and Roehm appeared together, in public, for the last time on April 17.  In the same month, Hess, Heydrich, Goebbels and Goering were actively working to bring down Roehm; Himmler was reluctant but joined. It was announced, on June 7, that the SA would take a month-long leave.  Hitler later told the Reichstag that he had met with Roehm, for five hours, at the beginning of June, and said
I informed him that I had the impression from countless rumours and numerous declarations of faithful old Party members and SA leaders that conscienceless elements were preparing a national Bolshevist action that could bring nothing but untold misfortune to Germany...I implored him for the last time to voluntarily abandon this madness and instead to lend his authority to prevent a development that, in any event, could only end in disaster.
Other leftist Nazis
Other political opponents
In particular, left-Nazi Gregor Strasser, The editor of Mein Kampf, Father Bernhard Stempfle, was thought to know too much. was targeted but escaped.
According to Lutze, Hitler decided to take action on the night of June 22, telling Lutze to take orders only from him. Himmler and Heydrich called an SS commander to Berlin, and put them on "unobtrusive alert." The Army agreed to give arms to the SA.
On June 28, Roehm was expelled from the League of German Officers. While the Army wanted the SA purged, they did not want to be personally involved. Hitler claimed, on the 29th, that he only intended to "deprive the chief of staff of his office and for the time being keep him and custody and arrest a number of SA leaders whose crimes were unquestioned..." On the night of the 30th, however, Hitler claimed he received "urgent messages" about an imminent SA coup. At the time, most of of the SA leadership were sleeping at the Halslbauer Hotel resort. Roehm had left his guards in Munich. Himmler, who had just told Joachim von Ribbentrop that "Roehm was as good as dead", said the Berlin SA would start to occupy government buildings at 5 PM. Adolf Wagner, Gauleiter of Bavaria, said the SA were in the streets.
The Night of the Long Knives actually began just after dawn, when a group, led by Hitler himself, drove from Munich to the Hanslbauer Hotel. One SA leader and his bedmate were immediately shot, but others, including Roehm, were brought back. Hitler had personally told Roehm, using the intimate form of German, "Ernst, you are under arrest." 
Roehm was taken to Stadlheim Prison, where Hitler gave him a last chance to commit honorable suicide. Roehm told the men who had brought him a loaded gun, "If I am to be killed, let Adolf do it himself." After a waiting time, the officers, Theodor Eicke and Michael Lippert, shot him to death.
Hundreds of other SA men were shot, but the purge went well beyond the SA, eliminating many of Hitler's political opponents, as well as some most hostile to the leaders, Goering and Himmler.
In explaining the actions, much indignation was voiced at the depravity of the SA leader. Sepp Dietrich said the situation in which Heines and a young bedmate were arrested and immediately shot, "defied description." Shirer said, however, that Hitler knew the situation well, including that Heines would send SA men all over Germany to find him new lovers. 
- William Shirer (1960), The Rise and Fall of the Third Reich, Simon & Schuster, p. 217
- Joachim C. Fest (1973), Hitler, Harcourt Brace Jovanovich, pp. 474-475
- John Toland (1976), Adolf Hitler, Doubleday, pp. 331-332
- Shirer, p. 216
- Fest, pp. 478-479
- Shirer, pp. 220-221
- Toland, p. 339
- Shirer, p. 225