Gaza City (CNN) -- Israel's ground incursion into Gaza, which it says is intended to destroy Palestinian militants' tunnels and stop rocket fire into Gaza, has entered its fifth day with the death toll mounting on both sides and U.S. Secretary of State John Kerry arriving in Egypt. CNN's Ben Wedeman, a veteran Middle East correspondent, puts the incursion into perspective.
How does this incursion compare to previous ones by Israel into Gaza, in terms of military force?
Unlike 2008/09, this incursion seems to be focused on areas with high concentrations of people, initially focusing on the Gaza City neighborhood of Shaja'ia. In '08/09 the focus was on areas where rockets were being fired, which were typically away from highly populated communities.
And of course at this stage, it's unclear how many Palestinian casualties there have been in these locations. The people have been warned by the Israelis to leave these areas with phone messages, but while many have left, a significant proportion has stayed behind.
My impression is that Israel has mobilized a much larger military force than in 2008/09 and in 2012. This is part of the picture of the Israelis going into heavily populated areas -- which is a much more dangerous operation, as can be seen by the deaths of at least 13 Israeli soldiers on Sunday.