Israeli forces are searching for a soldier believed captured, as a Gaza truce with Hamas collapsed just hours after it began.
The soldier, named as Hadar Goldin, 23, went missing when Israeli forces trying to destroy a suspected militant tunnel were attacked, Israel’s military said.
Israel and Hamas accused each other of breaching the 72-hour ceasefire.
Palestinian sources said at least 35 people were killed by Israeli shelling in the southern town of Rafah.
In 2006 Palestinian militants captured Israeli soldier Gilad Shalit and held him for five years.
He was released in November 2011 in exchange for 1,000 Palestinian prisoners.
Hamas has not commented on the latest reported capture.
Some 1,460 Palestinians, mostly civilians, have died in the latest conflict and 63 Israelis, mostly soldiers.
The ceasefire had been brokered by the US and UN to give civilians a reprieve from the violence, and had been seen as an unforeseen breakthrough after days of diplomatic deadlock.
Also on Friday, Palestinian and Israeli delegations arrived in Cairo, Egypt, with the hope of negotiating a longer-term cessation of hostilities, but Egyptian officials said the talks had now been postponed.