According to Hadith in Abu Daud with a Saheeh Sanad it is narrated Upon the authority of Ali Bin Abi Talib Radi Allahu Tala Anhu that:

A Jewish woman used to commit blasphemy against prophet Muhammad SallAllahu Alaihi Wasallam. A man killed her for this act. Upon getting news of this prophet Muhammad SallAllahu Alaihi Wasallam declared that the murderer should not be killed.

The above hadith clearly states that anyone who commits blasphemy against prophet Muhammad SallAllahu Alaihi Wasallam is to be killed in an Islamic government according to shariah.

Jamaat-ul-Muslimeen believes that committing even the slightest of blasphemy against prophet Muhammad SallAllahu Alaihi Wasallam is kufr.