During the current round of fighting in the Gaza Strip, Kareem, a 40-year-old Palestinian, witnessed a Hamas tunnel exposed.
"There is a chicken coop near us," said Kareem, who lives on the eastern edge of Gaza City, bordering on farmland. "We know it's a chicken coop."
But an Israeli attack, which destroyed the chicken house, revealed a tunnel heading east toward Israel, he said.
"We didn't know about it, but we faced a risk because of it," he said.