CNN reporting that the bomb exploded on the bus at it passed Israeli army headquarters at around noon. Initially, there were suggestions that it might have been a suicide bomber. But that does not appear to the case. Hamas praised the bombing but did not take claim responsibility. There is also a report of an unexploded bomb that remains on the bus: www.cnn.com

One of the key questions: could the Tel Aviv bus bombing derail ceasefire efforts?

This is the first bombing in Tel Aviv since 2006, according to AP. Also, here is the Hamas comment following the bombing: "We consider it a natural response to the occupation crimes and the ongoing massacres against civilians in the Gaza Strip," Hamas spokesman Fawzi Barhoum told The Associated Press. But no claim of responsibility from Hamas - or any other group yet.

For those who know Tel Aviv, here is the location of the bombing, according to Haaretz newspaper: at the corner of Shaul Hamelekh and Henrietta Szold Streets.

Haaretz reporting that following the bombing: "Police opened an immediate manhunt for two suspected terrorists." Here is the rest of the story: www.haaretz.com

Let's focus on Gaza for a moment - and look at some of the developments there before the Tel Aviv bus bombing and after.

Thast last tweet is from the Israeli Defense Forces Twitter account - indicating that one out of three rockets fired at Israel was destroyed by the missile defence system called Iron Dome.

The Globe's Omar El Akkad is in Cairo, Egypt - reporting from there on what is looking to be a crucial day if a ceasefire deal is to be reached. But there are street protests under way in Cairo as well, as Omar points out.

So those Cairo protests not connected directly to events in the Israel-Gaza conflict. But Cairo is also where a big push is underway. Set the scene for us in terms of the diplomatic efforts – there was talk of an imminent deal yesterday, what went wrong?

Primarily, what went wrong today was the bombing of a city bus in Tel Aviv. Yesterday, it appeared an Egyptian-brokered deal was imminent, with disagreements on both sides regarding some aspects of the deal, but nothing insurmountable.Today, perception alone might be enough to set the ceasefire back.. Even though it's not clear if the Tel Aviv attacker came from Gaza (or, more likely, the West Bank), a bus bombing likely leaves Israel much less likely to agree to the same deal today it had on the table yesterday..

Omar, I guess that is going to be key – whether the Tel Aviv bombing derails the ceasefire talks in Cairo. But just on the talks – this is not a situation where the parties are speaking directly to each other, they are going through Egyptian intermediaries right?

So the Globe's Omar El Akkad is in Cairo, Egypt - where frankly there are two big stories unfolding: ceasefire talks that the Egyptians are holding to reach an agreement between Israel and Hamas. The other story involves street protests on the one-year anniversary of anti-government clashes - not linked to the ongoing Israel-Gaza conflict.

Because the United States considers Hamas a terrorist entity, Washington won't speak to the group directly. That's why Egypt's role in the process is so vital. In some ways, the role of peace-broker falls to Cairo by default. Despite it's post-revolution instability, Egypt is still hugely influential in the region, and ties between Mr. Morsi's Muslim Brotherhood allies and Hamas are strong. The country also has a peace agreement with Israel. As such, Cairo is the central conduit between Washington and Hamas in this process. .

A question about the Egyptian president, Mohamed Morsi, a lot of people were skeptical about the role he was going to play in the Israel-Gaza conflict. But if he can help broker a ceasefire, he comes out of this looking like a dealmaker and reliable partner?

If President Morsi pulls off a ceasefire agreement, he will have managed a very delicate balance. Early on, his overt support of Hamas -- which included sending his foreign minister to Gaza and allowing Egyptian activists to enter the region -- set him apart from ousted former President Hosni Mubarak and helped placate the Muslim Brotherhood. It also earned him some praise from everyday Egyptians, who are overwhelmingly opposed to Israel's shelling of Gaza. However, many members of the Brotherhood would prefer he go even further. And if the shelling of Gaza intensifies, many more Egyptians will likely take the same position. But to do so, Mr. Morsi risks Egypt's peace with Israel, as well as upsetting Washington, which could cut aid to the country. As such, the sooner Mr. Morsi can arrange a ceasefire, the sooner he can give himself some breathing room. .

And just a word on Omar's analysis there about Egypt's president, Mohamed Morsi, and his efforts at "a very delicate balance" in managing his government's response to the Israel-Gaza conflict: if Mr. Morsi can negotiate a ceasefire deal, he comes off looking quite agile, cooperative, and will get plenty of kudos from Washington, where the Obama administration has already praised his efforts.

Thanks, Affan. Let's begin with an update on what's been happening in Gaza today.

More from AFP: Shortly afterwards, another air strike on Nusseirat refugee camp in central Gaza killed a four-year-old girl and wounded her mother, the emergency services told AFP.

Earlier, six people were killed in other strikes on Gaza City, one person in a raid on the Jabalia refugee camp and an 80-year-old man and his teenager granddaughter in a raid on the southern city of Khan Yunis.