What is the "Nurcu" group and what is the ruling on reading their books?

The Nurcu movement is an Islamic religious group, closer to Sufi orders, founded by Sheikh Said al-Nurcu to confront the secular wave in Turkey after the fall of the Ottoman Caliphate. His call focused on faith and the purification of souls. He suffered imprisonment and torture for his opposition to secularism. The Nurcu youth are known for their chastity and purity. However, the group did not focus on spreading the creed of the Salaf, adopted Maturidism, sometimes abandoned politics, and did not establish organized Islamic work against Jewish cunning. Its followers numbered over a million people. Reading their books is not recommended except for specialists and distinguished students of knowledge, due to their creed differing from that of Ahl al-Sunnah wa al-Jama'ah, despite the commendable efforts of their Sheikh.