Palestinian groups expect Israel to flood Hamas tunnels with a type of nerve gas or chemical weapon under the surveillance of US Delta Force commandos as part of a surprise attack on the Gaza Strip, a senior Arab source familiar with the Palestinian groups told Middle East Eye.

Israel and the US hope to achieve the element of surprise in order to penetrate Hamas tunnels, rescue an estimated 220 hostages, and kill thousands of soldiers belonging to Hamas’ al-Qassam Brigades, the source said, noting that the information they received came from a leak originating in the US.

Middle East Eye cannot independently verify the information in the leak.

"The plan hinges on the element of surprise so as to decisively win the battle, using internationally forbidden gases, particularly nerve gas, and chemical weapons. Large quantities of nerve gas would be pumped into the tunnels," the source said.

The source added that the US Delta Force will oversee "large quantities of nerve gas being pumped into Hamas tunnels, capable of paralysing the bodily movement for a period of time between six and 12 hours.