A tunnel along the Egypt, Gaza border used to convey commercial goods collapsed on Thursday as a result of Egypt's deliberate flooding of the area in recent months.
The Hamas-affiliated Arsala website in Gaza reported seven Palestinian workers were missing, but six were later found. A security source in Gaza said the Palestinians who were in the tunnel near the town of Rafah were not members of their organization's military arm.
The report said the tunnel that caved in was controlled by several families identified with Hamas, and had been used mainly to smuggle in goods and people into Gaza.
Palestinian rescue services who reached the site complained that they lacked the necessary equipment to deal with the collapse.
Relations between Hamas and the Egyptian authorities have significantly worsened since President Abdel-Fattah al-Sissi rose to power in 2013. This week suspects held for the death of Egypt's general prosector Hisham Barakat in a June car bombing, said they had been trained by Hamas activists in Gaza for more than six weeks.
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