I do not believe Martin Luther King, Jr. supported the violent efforts of other minority leaders. He believed in their opinions but King was in support of peaceful efforts to make change, not violence. King made the abundantly clear over and over again, despite what these other leaders did and despite what some of his followers did.
Martin Luther King Jr. did not support the violent efforts of other minority leaders. King believed that ultimately, non-violence was a more effective strategy long term, though he had trouble convincing other leaders that non-violence is not a cowardly act, but instead seeks to win its opponents' friendship and understanding, whereas a violent leader would seek to destroy and humiliate their opponents. King believed that at the end of the day, minority and non-minorities would one day bridge the gap of social injustice and this goal would be easier achieved with non-violent acts.
There was a split within the civil rights community over the issue, but Dr. King was emphatically against violence in people protesting, and that's why he is the legend he is. Anyone who can purely support peaceful protest for their rights is a true hero, and he was definitely one.
No, Martin Luther King, Jr. likely did not support the violent efforts that were being conducted by other African American leaders at the time. Martin Luther King, Jr. promoted ideas of peace and equality, but he promoted his beliefs through non-violence. He also encouraged others to take a stand, but to do so peacefully (by non-violent means).
I do not think that Martin Luther King, Jr. Supported the violent efforts of other minor leaders. I think he was a peaceful man that wanted things to be resolved, but done correctly and in the right way. I think he saw all people as equal and loved them all.