The military wing of Hamas continues to be helmed by the Muhammed Deif, who serves as a chief of staff, while Yahya Sinwar serves as a defense minister and liaison with the political wing. Under them, Marwan Issa, Deif’s aide de camp, deals with building up the group’s military capabilities. Reporting to Issa are various commanders of different brigades and areas, such as defense industries and others.“
(Avi Issacharoff: „Hamas spends $100 million a year on military infrastructure“)