Relations between Akbar and Guru Arjan were cordial but things changed after the accession of Jahangir. Ultimately the Guru was tortured in 1606.[4] Sikhs believe that, having obtained leave to bathe in the Ravi river, he vanished, to the fear and wonder of those guarding him. Many reasons have been given for this tragedy. It is stated that Jahangir was annoyed because Guru Arjan gave his blessings to his rebel son, Prince Khusrau Mirza. Jahangir also did not like the growing popularity of Sikhism and took strong objection to conversion of Muslims to Sikhism You can read more on Wikipedia