What is the ruling on one who says that the Qur'an is human speech, and is he to be killed for that?

The creed of the Salaf and the People of the Sunnah is that the Qur’an is the revealed Speech of Allah, uncreated. From Him it originated and to Him it will return. Allah spoke it in reality with a voice, and Jibril heard it and descended with it to Muhammad (peace be upon him). Whoever says the Qur’an is created, or that its meaning is the Speech of Allah but its letters are not the Speech of Allah, is a disbeliever (kafir) and an apostate (murtad). However, a specific person is not to be judged as a disbeliever until the conclusive proof (al-hujjah ar-risaliyyah) is established against him and any doubt (shubah) is removed. If the proof is established and the person persists in his saying, then he is a disbeliever and an apostate, and the ruler (wali al-amr) has the right to execute him after seeking his repentance. Individuals among the populace are not permitted to carry out Hadd penalties without the permission of the ruler.