Hamas has begun using heavy machinery and engineering tools to accelerate the excavation of attack tunnels leading from the Gaza Strip under the Israeli border, sources in the Palestinian enclave told the Times of Israel Wednesday.

The equipment, the sources said, includes small bulldozers with the ability to maneuver in tight spaces. From the Israeli side of the border, larger tractors are clearly visible above the ground as the machines prepare the tunnel entries.

The Gaza-based terrorist organization has been using whatever cement it can get its hands on for the construction of the tunnels, and fortifying the walls of its underground structures with wood as well.

Israeli security officials confirmed the reports from Gaza, adding that Hamas was making great efforts to dig the tunnels at high speed.

The officials also said the terror organization was attempting to produce as many short-range rockets as possible, after noting that these projectiles were less likely to be downed by the Iron Dome defense system and could therefore cause substantial damage on the Israeli side.

A report in the Telegraph earlier this month said Iran was transferring tens of millions of dollars to Hamas to rebuild its underground infrastructure and replenish its rocket arsenal. Israeli security sources in March said that Hamas has invested considerable effort in digging a new tunnel network within the coastal enclave, as well as several tunnels meant for eventual cross-border attacks. But according to those sources, the terror organization was being careful to avoid crossing into Israeli soil, in order to avoid an eruption of hostilities.

Meanwhile, the physical and economic situation of Gaza’s residents hasn’t changed much. Heavy rains earlier this week left several main streets in the Strip flooded. Temporary housing units for refugees who fled their homes after this past summer’s war between Israel and Hamas were flooded as well. The Rafah border crossing from the Gaza Strip into Egypt remains shut, and the ongoing wage crisis involving Hamas and the Palestinian Authority has not been resolved. The general reconstruction of Gaza continues to be delayed, and the rebuilding of 17,000 houses to replace the those destroyed during Operation Protective Edge has not yet started either.

The main reason for this impasse is the power struggle between the Palestinian Authority and Hamas over control of the Gaza Strip. The PA has demanded that Hamas cede allgovernance activity in the Strip, including security operations, to Rami Hamdallah’s government, but the organization has refused to do so.

For now, the immediate dispute between the two Palestinian parties revolves around the payment of salaries to Hamas government officials, and the PA has so far been unwilling to cover the costs. Twenty-three thousand Hamas officials, including employees of the health and education systems, have not received their wages. The salary dispute has been raging since the signing of the reconciliation agreement between Hamas and the PA in April 2014 — which has not yet been implemented (notwithstanding false accusations by Israeli officials implying that PA President Mahmoud Abbas essentially incorporated Hamas in his government).

Among other steps aimed at resolving the crisis, PA Deputy Prime Minister Ziad Abu Amr resorted to asking the Swiss government to  mediate between the two quarreling Palestinian sides. Swiss diplomats, led by Paul Garnier, the representative of Switzerland in Ramallah, met with Hamas and PA officials, and in September produced a road map agreement in an attempt to end the lengthy dispute.

Under the agreement, official commissions were to determine the identity of those on payroll in Gaza (in order to prevent wages from being delivered to terrorists, for example, or to people who are no longer employed), and at the same time to enact reform in government offices. Last October, Qatari officials provided the Palestinian Authority with enough cash to allow for the payment of salaries, but the final transfer was cut short after explosive devices were placed near the homes of Fatah activists in the Gaza Strip, setting back the Swiss efforts.

In recent weeks, efforts were again resumed to resolve the crisis.

This month, Hamas was able to pay wages to its employees, though it is unclear how the organization managed to acquire the funds.