Here´s the official statement posted from the man himself on POSSESSION official facebook:
"I, Mestema / vocals, have decided to leave Possession as from now on. The band is not dead at all though and its remaining members will soon post information about the future of the band. I would like to stress on the fact that there is no bad blood between us. The reasons why I took this decision are not your business so do not waste your time asking. I would like to thank those who have supported me / us since the beginning and wish Possession the best.
December 2012 - September 2015"