Gaza officials say four Palestinians suffocated on Tuesday while trying to repair a smuggling tunnel hit in an Israeli airstrike last week.
Under Hamas rule, hundreds of underground channels have been dug between Gaza and Egypt, used for smuggling goods and people into the Gaza Strip, which is blockaded by Israel.
Hamas and Gaza health officials said the four Palestinians died as they worked underground.
Israel struck several tunnels in Gaza recently, after a Hamas mortar attack on an Israeli school bus led to retaliatory air strikes on the Strip. The workers were apparently killed while repairing one of these tunnels.
Since June of 2007, over 100 Palestinians lost their lives in tunnel collapses.
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