I consider Mirza Ghulam Ahmad Quadiani to be an impostor nabi and also consider his followers whether belonging to the Lahori or Quadiani group, to be NON-MUSLIM.
(declaration all Pakistani Muslims have to sign in order to get a passport¹)
The Ahmadiyya is a religious sect originating in the Punjab. Mirza Ghulam Ahmad began the movement in 1899, starting in his home village of Qadian.
He was a learned defender of Islam, and also studied other religions in order to see what was right and wrong in them. All this was well and good. The trouble started when the teacher had several visions of God and proclaimed himself a prophet. He set out to rejuvenate Islam and preached a great deal of things, such as the fact that
Jesus was buried in Srinagar.
A major problem for other Muslims, however, was his statement that he was a Messiah and a prophet. According to the Quran, there could be no more prohpets after Mohammad, and anyone who declares he is one is therefore a heretic. Ahmad later retracted his claim to prophethood, saying he had not spoken literally. Now there are two schools of Ahmadiyya: The Qadiani chapter, who still think the teacher a prophet, and the group of Lahore, who say he was only a religious leader.
Still, merely following his teachings makes a person suspect in the eyes of mainstream Muslims. Since Pakistan is supposed to be a pure, Muslim country, Ahmadiyya is not at all acceptable. Being an Ahmadiyya and still calling oneself a Muslim is considered blasphemous.
Numbers of the Ahmadiyyas range from "a few thousands" to "10 million", depending on whether you ask a protester or a supporter. The religion is strongest in the Pakistani city of Rahwab, but has also spread to other parts of the world, from South-East Asia and all the way to America.