"The fucking haji's are real friendly in the day time waving, smiling and shit- but at night they go plant IED/VBIED on the streets"
-"stupid haji's, try so hard, yet succeed so little."
It is most commonly used in an ironic manner toward Muslims who have not completed Haj, and has expanded to a general derogatory term for Arabs.
However the title is an honor to those who have completed Haj, and is not restricted to any single ethnicity.
Muslims in eastern Europe may be offended by to be called "Haji", since many erroneously consider all Muslims to be Arabs.