24 August 2014 :

one day after Israel killed three top Hamas commanders, the radical group executed 18 Palestinians it had suspected of collaborating with Israel. It brings the number of alleged informants executed in the past two days to at least 21, including several people arrested in relation to the killing of the three Hamas commanders.
At least 11 people, including two women, were executed by firing squad in al-Katiba prison yard in the west of Gaza City after being sentenced to death in Gaza courts, Globe and Mail reported.
A witness and Hamas media said that masked gunmen had killed another seven suspected informants for Israel near a Gaza City mosque as worshippers were ending midday prayers, reported the Associated Press. A piece of paper nailed to the wall of the mosque said they provided the enemy with information about tunnels, houses and locations where rockets were held, which were then bombed causing the death of many Hamas fighters. “As a result the judgment of the revolutionary court was implemented,” the note read.
The identities of those executed is not yet known as the victims had their heads covered. The Hamas-run website Al Rai warned that "the same punishment will be imposed soon on others". (Sources: AP, G&M and AI, 22/08/2014)