A true mujahid is one who is pious, never takes innocent lives, never afraid of any one expect Allah, always repents for his deeds, and moreover no one is harm from his deeds.
But today, the word Majahid is use to describe those who don't have above mention qualities. I ask all to first read Holy-Quran to know what it has to say about all this, since Quran is the only source from wheir all these Mujahid's get spiritual energy.