The recent Gaza clashes demonstrate that when these so-called renegade groups launch rockets or plant bombs, and get caught by IDF patrols - Hamas snipers are there all along to give them cover fire. So Hamas is not preventing attacks on Israel, but is encouraging and enabling them. The "unnamed groups" in reality don't even exist, they are Hamas operatives. Rockets and IEDs are not as easy to build as the media woulds have us believe. Just a Hamas PR stunt to continue firing while blaming others.
Report: Man detained at Newark Airport after entering secure area, prompting evacuation (Haaretz)
from the article: Four Gaza factions halt rocket fire, in bow to Hamas