Jerusalem, Nov 4 : Israel has claimed responsibility for an attack outside the Al-Shifa Hospital in Gaza City, the largest in the enclave, saying that a fighter jet had struck an ambulance used by Hamas personnel. In a post on X late Friday, the Israel Defense Forces (IDF) said: "A Hamas terrorist cell was identified using an ambulance. In response, an IDF aircraft struck and neutralized the Hamas terrorists, who were operating within the ambulance. We emphasize that this area in Gaza is a war zone. Civilians are repeatedly called upon to evacuate southward for their own safety." In a separate statement, the military said that the ambulance was "being used by a Hamas terrorist cell in close proximity to their position in the battle zone". 'A number of Hamas terrorist operatives were killed in the strike. We have information which demonstrates that Hamas' method of operation is to transfer terror operatives and weapons in ambulances," CNN quoted the statement as saying. But the UN Relief Works Agency (UNRWA) has said that "a convoy of ambulances evacuating patients from Shifa hospital in Gaza city to the Rafah crossing with Egypt, was struck three times in the vicinity of the hospital". Citing initial reports, the UN body said that at least 13 people were killed and 26 injured. Earlier Friday, a spokesman for the Gaza-based Palestinian Health Ministry had also said that the ambulance was in a medical convoy from the hospital, traveling to the Rafah border crossing, and had informed the International Committee of the Red Cross about the move. On its part, the ICRC confirmed it was aware of the scheduled movement of a convoy of vehicles carrying wounded patients from northern Gaza to the south, but it was not part of it. "We were informed by the MoH (Ministry of Health) about the planned convoy, but we were not part of it," the ICRC told CNN. "Even if we were not present, this is still medical convoy, and any violence towards medical personnel is unacceptable... No doctors, nurses, or any medical professionals should ever die while working to save lives." As a result of the severe shortage of fuel in the Hamas-controlled enclave, one of the generators in the the Al-Shifa Hospital reportedly stopped working on Friday, according to the UNRWA. Another generator is still operating, but it is only covering about half of the hospital's needs, it said. Since the start of hostilities, 14 out of 35 hospitals with inpatient capacities have stopped functioning and 51 (71 per cent) of all primary care facilities across Gaza (72) have shut down due to damage or lack of fuel. /IANS