So they just take over these missile workshops like the Soviets did of Nazi work/death-camps after WWII.
Hamas security forces have uncovered a rocket workshop run by a pro-Islamic State organization in Gaza, according to a jihadist in the coastal enclave.
Salafists include a number of ultraconservative Islamic groups that seek to turn Gaza into an Islamic caliphate. These groups have created a headache for Hamas in recent years, accusing it of being too soft on Israel and of failing to adequately impose religious law.
More here. H/T: Jihad Watch