Emergency workers have recovered the bodies of three Palestinians who went missing in a smuggling tunnel between Gaza and Egypt.
Search efforts were still ongoing Sunday for a fourth who is still missing.
The Al-Aqsa Radio, run by Gaza's Islamist Hamas rulers, reported that the tunnel caved in after the Egyptian military flooded it with water. There was no comment from the Egyptian army, which had swamped the tunnels last year but has rarely done so in 2016.
Cross-border smuggling, which kept Hamas buoyed for years, has come to a near-total halt after Egyptian forces destroyed most of the tunnels as part of its clampdown on mounting insurgency in the northern Sinai Peninsula.
Hamas overtook Gaza by force in 2007 after routing troops loyal to Palestinian President Mahmoud Abbas.