Speculation is growing that a ground invasion by Israel in Gaza is becoming increasingly likely. The BBC [2] is reporting that Israel has put 75,000 reservists on stand-by, and deputy foreign minister Danny Ayalon told CNN [3] that an invasion could happen before the end of the weekend:

"We don't want to get into Gaza if we don't have to. But if they keep firing at us … a ground operation is still on the cards," he said. "If we see in the next 24 to 36 hours more rockets launched at us, I think that would be the trigger."

Watch his interview in full:

Israeli air strikes are continuing on the Gaza strip. Reuters [4] reports that the office building of Prime Minister Ismail Haniyeh - where he had met on Friday with the Egyptian prime minister - was hit, as was the house of a Hamas leader in Jabaliya, north of Gaza City.

Egypt's president, Mohammed Morsi, called the attacks on Gaza [5] "a blatant aggression against humanity" and said that "Egypt will not leave Gaza on its own". President Obama has praised [6]Egypt's efforts to "deescalate" the tensions in the region.

The hundreds of tunnels in the south of Gaza, which are used to smuggle food, fuel and weapons from Egypt, have also been targeted by Israeli air strikes, the Guardian [2]reports. The Israeli military say that over 800 targets have been struck since the operation began (Associated Press [7]). It's thought that about 500 rockets have been fired towards Israel.

At least 38 Palestinians and three Israelis have died since Israel killed Hamas's military commander [8] on Wednesday.