A year of information-gathering by Military Intelligence and the Shin Bet (Israel Security Agency) paved the way Saturday for Operation Cast Lead.
At 11:30 a.m., more than 50 fighter jets and attack helicopters swept into Gazan airspace and dropped more than 100 bombs on 50 targets. The planes reported "alpha hits," IAF lingo for direct hits on the targets, which included Hamas bases, training camps, headquarters and offices.
Thirty minutes later, a second wave of 60 jets and helicopters struck at 60 targets, including underground Kassam launchers - placed inside bunkers and missile silos - that had been fitted with timers.
Their locations were discovered in an intensive intelligence operation. The goal: to strike at Hamas's ability to fire rockets into Israel.
More than 170 targets were hit by IAF aircraft throughout the day. At least 230 Gazans were killed and over 780 were wounded, according to Palestinian sources. Officials said at least 15 civilians were among the dead.
The IDF released a list of some of the targets hit: the Hamas headquarters and training camp in Tel Zatar; the "Palestinian Prisoner Tower" in Gaza City that was turned into a Hamas operations center and armory; the Hamas police academy, which was bombed during a graduation ceremony, killing 70-80 people; training camps in southern and central Gaza; the former office of Yasser Arafat in Gaza City that is now used by Hamas Prime Minister Ismail Haniyeh; and the Izzadin Kassam Brigades headquarters in the northern Gaza Strip.
Throughout the initial stages of the air operation, the IDF Gaza Coordination and Liaison Administration transmitted messages to civilians in Gaza to stay away from Kassam launch sites and Hamas buildings and infrastructure.
AP contributed to this report