Israel, Gaza and the United States are trading blame for the rapid failure of the 72-hour cease-fire that was supposed to begin Friday morning at 8 local time (1 a.m. EDT). Two Israeli soldiers were killed in an attack in a Rafah tunnel and one, Lt. Hadar Goldin, is feared to have been captured by Hamas militants. He is rumored to be both an Israeli and British citizen.

Following the attack, Israeli shelling rained down on Rafah at the southern end of the Gaza Strip, killing at least 50 Palestinians and wounding hundreds more.

Despite the broken truce, Palestinian Authority President Mahmoud Abbas said he is still preparing a 12-person delegation that will travel to Cairo Saturday for cease-fire negotiations. The group will include members from Abbas's Fatah, the West Bank’s ruling party, Hamas and Islamic Jihad, an even militant Islamist group in Gaza. Abbas said the delegation is going “whatever the circumstances.”

Hamas is not taking responsibility for ending the cease-fire, and said Israeli troops violated it by advancing in Rafah after the cease-fire had begun.

"There has not been any Israeli soldier in eastern Rafah for the past 20 days. But as soon as the cease-fire was announced, Israeli movement in the area began at around 2 a.m., 2.5 kilometers into eastern Rafah," said Fawzi Barhum, spokesman for Hamas’ military wing, the Izz al-Din al-Qassam Brigades. "In response to that, our fighters clashed with Israeli soldiers in Rafah at 7 a.m., killing and injuring many."

"It is the occupation which violated the cease-fire. The Palestinian resistance acted based on ... the right to self-defense, to stop the massacres of our people," the statement said.

Israel Defense Forces spokesman Lt. Peter Lerner told the BBC that the Israelis had no choice but to attack. According to the cease-fire terms, all forces were to stay in place but to pause all attacks. It was not specified whether or not Israel could continue destroying the tunnels, as it did during the last cease-fire.

"We were holding our fire, we were implementing our part, held all of our forces, stopped aerial assaults,” Lerner said. “And indeed what happened was they came out while we were dealing with one of these tunnels. ... We have no other choice now but to operate and pursue them."

White House Press Secretary Josh Earnest condemned the alleged capture of the 23-year-old Goldin on CNN, calling it a “barbaric violation of the Gaza cease-fire.” He called on Hamas to return the Israeli soldier.

Israeli's response to the capture could mean be a new surge of attacks on the Gaza Strip, where the Palestinian death toll is at least 1460. Sixty-three IDF soldiers have been killed.

“Hamas has paid, and others will pay, a heavy price,” Justice Minister Tzipi Livni said. “And if it wasn't sufficiently clear before, the world now knows who is responsible for the destruction and bloodshed in Gaza.”