Hamas has been severely shaken by string of Israeli airstrikes targeting its most senior leadership in Gaza, and is continuing a witch-hunt against suspected "collaborators" in an effort to ascertain how Israel knew of their whereabouts despite their best efforts to remain undetected.
Following a spate of at least 25 executions carried out by Hamas in Gaza against suspected "collaborators" with Israel, Hamas has arrested at least 150 more suspects, according to the Al Bawaba news site.
Hamas's "military wing", the Ezzedine al-Qassam Brigades, issued a statement on Sunday saying that the men had been arrested over "security leaks", a source told the Arabic-language outlet. The source claimed Hamas was "in a state of confusion" following the elimination of three top al-Qassam Brigades commanders, Mohammed Abu Shamalah, Raed al-Attar and Mohammed Barhum on Thursday, as well as an attempted assassination of the Brigades's top leader, Mohammed Deif.
Hamas claims Deif survived the attack, which killed his wife and two of his children, but has not issued any word on his condition.
Compounding the group's fears is the fact that the Israeli Air Force strike killed Abu Shamala, Attar and Barhum as they met in a top-secret bunker some 30 meters underground. Six other commanders were reportedly due to join them, but the decision appears to have been taken to eliminate them as soon as they were together, to avoid the possibility of any of them getting away.
And the assassinations of top Hamas leaders has continued since, with the group's top financial chief and "Justice Minister", Mohammed al-Ghoul, taken out by an Israeli airstrike on Sunday.
The bunker was located under the home of the "Kilab" family, and the IAF targeted the house and the tunnel beneath it with bunker-buster bombs weighing up to three tons, both ensuring the elimination of the terrorists and avoiding unnecessary damage to surrounding homes as much as possible.
Their liquidation essentially wiped out Hamas's entire southern military command in Gaza.
The executions, which mostly took place over last Friday and Saturday, have been condemned by NGOs spanning the left and right with some comparing the public killings to those carried out by the brutal Islamic State group (formerly ISIS) in Iraq and Syria.