● Hamas tunnelling back at pre-2014 levels
● Terror group rebuilding missile stocks
● Iran increases funding for Gaza militants

After a relatively calm year around the Gaza Strip, Israel is concerned that an escalation down south is approaching once again.

In recent weeks, Israeli intelligence has updated its assessments of the progress made by Hamas in rebuilding the tunnels destroyed by Israel during the 2014 Gaza conflict.

The IDF now thinks that the terror group's tunnelling infrastructure is at least as extensive as the network that existed before the war.

Israeli security officials also believe that Hamas's military wing plans to use the tunnels at the start of the next confrontation to carry out a wide-ranging attack on civilians and military bases.

Hamas has devoted a large part of its resources to replenishing its missile arsenal, and recently carried out test launches towards the Mediterranean.

In 2015, 27 rockets were fired towards Israel, but almost all came from smaller Salafist groups, some of which are aligned with Daesh. Hamas has often blocked or - in some cases - arrested them.

Last Wednesday, Israeli aircraft attacked a team trying to lay explosive devices on the border fence, north of Gaza. They were identified as members of a Salafist group, but Israel has detected a growing reluctance on the part of Hamas to stop them.

While Hamas's political leadership is more focused on keeping internal control and rebuilding civilian infrastructure, the military wing, now receiving increased financial support from Iran, is planning the next round of fighting.

Within the Israeli leadership, meanwhile, there is disagreement over the best approach towards Gaza.

The official line is that Israel should continue isolating the Hamas-dominated Strip, in co-ordination with the Egyptian government, which regards Hamas as a hostile force in cahoots with Daesh in Sinai.

Some experts in the defence establishment believe that Israel should encourage infrastructure projects in Gaza - even though some of the building materials are certain to be used for Hamas tunnel-building - in the hope that it will give the Palestinians an incentive not to resume fighting.

Hamas has remained largely on the sidelines of the violence between Israel and the Palestinians in recent months.

Its spokesmen have encouraged civilians to attack Israelis and congratulated terrorists who succeeded in killing civilians and soldiers - but due to its lack of a military infrastructure in the West Bank, it has largely failed to carry out its own terror missions.

In Gaza, Hamas has largely made do with encouraging civilians to march towards the border fence, where confrontations with Israeli soldiers have resulted in dozens of casualties. On Friday, in one such demonstration, two young Palestinian men were killed and 10 others injured, according to Palestinian health ministry, when the IDF opened fire on a group trying to tear down the fence.