What is Israel's strategy in Gaza?
Israeli officials say the military has broadened the scope of its operation in the Gaza Strip and is preparing for a ground offensive in case one is ordered.
On Friday, the cabinet authorised the call-up of up to 75,000 reservists, although so far only about 20,000 have been contacted.
So what is Israel's military strategy?
Its offensive, which is being called Operation Pillar of Defence, began on Wednesday when the head of the Hamas armed wing, Ahmed Jabari, was killed in his car in Gaza City.
Since then, the assault against Gaza has been conducted through a remote campaign of air strikes, naval artillery and tank fire across the border.
More than 1,100 targets have been hit. The Israel Defense Forces say their objective is to stop rocket fire by militant groups in Gaza into Israeli towns and cities.
Late on Sunday, Israel's Deputy Prime Minister Moshe Yaalon told journalists that Hamas, which governs Gaza, had to satisfy Israeli demands.
"It's up to them to make up their mind whether it is worse to go on with these rogue activities - firing rockets and terror activities," he says.
"We are looking for this kind of ceasefire which will bring about peace and quiet. We don't claim to topple Hamas, this not our objective. It is to deter them."
Leading defence correspondent Alex Fishman, who works for Israel's biggest circulation newspaper, Yedioth Ahronoth, says the offensive does not come out of the blue.
"There were plans for these events months in advance, so strategically it wasn't a surprise," he says. "The timing was due to what Hamas was doing along the Israeli and Egyptian borders, and then there were troubles the last couple of weeks.
"We are still on the first chapter, the aerial operation, which used precise weapons systems and the navy, towards targets that were stockpiled before by the army and intelligence.
"The next stage will be much more difficult because the air force will bombard the civilian areas. They keep a lot of rockets among civilians.
"The third stage will be much brutal bombardment, the ground forces invasion, [but] I believe that we won't reach this stage. The political and military leadership are not eager to go to such an elevation."
Mr Fishman argues the green light to call up large numbers of troops was important to apply diplomatic pressure, but does not mean that a wider operation was planned.I don't see a rush to ground operations but I would not rule it out eventually. At this point Israel is still shaping the battle space. Hamas seems eager for Israel to launch such an attack, so at this point the air attacks are frustrating those ambitions and wearing away at the ability of Hams to resist.
If I were in Israel's position I would consider a move along the Gaza-Egyptian border to cut off any resupply efforts. I would also do strikes at various points along the border to cut off and isolate Hamas fighters while the troops also clear buildings and search for weapons caches. Hamas is probably planning for an operation of a more conventional matter.
Once the troops are in, the Israelis need to establish a force to space ratio that makes it difficult for Hamas fighters to move to contact without detection.
Hamas's strategy has been to force Israel to allow an open border. The chances of an agreement that allowed that are remote.