The Palestinian group Fatah, which controls the West Bank simultaneously assists Israel in fighting Islamic terror groups that are a threat to Fatah while it also works, with a more hands off approach, with groups that have a special relationship with Fatah and are dedicated to destroying Israel. This includes a Fatah affiliated terror group, the Al Aqsa Martyrs Brigade which has long maintained a working relationship with Fatah by, for example, continuing to attack Hamas (which took control of Gaza in 2007 and wants to replace Fatah in the West Bank) as well as Israel.
Al Aqsa survives by finding useful allies wherever it can. Thus a recent video showing al Aqsa terrorists inside what was described as a 3,500 meter long tunnel from Gaza into Israel was part of an appeal for more aid from Iran. Hamas pioneered the construction of such tunnels but keeps quiet about that since losing a 50 Day War with Israel in August 2014. Unofficially Hamas is building its own tunnels and also seeks aid from Iran. Apparently Iran will supply such aid to both Hamas and al Aqsa as long as Hamas does not try to wipe out al Aqsa in Gaza. Thus Hamas is under pressure (from Israel and many Hamas supporters in Gaza) to pretend to go after al Aqsa despite the fact that al Aqsa keeps violating the Hamas ceasefire agreement with Israel by continuing to fire rockets into Israel. The Israeli retaliation attacks show that Israel knows what is going on here and these Israeli attacks usually just hit al Aqsa facilities. But recently Hamas targets have been hit as well because this make-believe effort to shut down the misbehaving al Aqsa in Gaza is getting old and Israel is unwilling to continue tolerating it.