From ABC's Sandra Petrykowski

PLO executive committee member Hanan Ashrawi lashed out at Israel today over what she described as "war crimes" and the "deliberate massacre" of Palestinian civilians during Israel's current ground offensive in the Gaza Strip.

"This morning, it's nothing short of a massacre, a deliberate massacre. War crimes committed daily. But now there is a deliberate shelling and bombing and destruction of whole areas, of residential areas," Ashrawi said on "This Week."

"These are war crimes being committed before the world, before the eyes of the whole world and I just can't understand how people sit back and say [it's] self-defense. I just can't take the language, I can't take the propaganda, I can't take the mantra that Israel has a right to defend itself. Against whom? Against innocent civilians? More than 80 children have been torn to bits. Is this self-defense?" Ashrawi added in her extended interview with ABC's Hamish Macdonald reporting today from Ramallah.

As of Sunday morning, more than 400 Palestinians have been killed - including at least 60 on Sunday alone - and more than 35,000 Gaza residents have been displaced since Israel launched Operation Protective Edge on July 8, in response to Hamas rocket fire into Israel. Eighteen Israeli Defense Forces troops have been killed in the latest ground offensive into Gaza, now in its fourth day.

"Look there, there is no human being who cannot be affected by this. Unless you lose the last vestiges of humanity, you cannot allow this to go on. It has to stop," Ashrawi said of the latest violence in Gaza. "And Mr. Obama, and the Congress, and everybody has to know that these are human beings. Think of your children. I'm a mother, I'm a grandmother. I cannot tolerate to see torn limbs. I cannot see grown men break down and sob. I cannot see people - a whole nation in a state of trauma."

READ: Benjamin Netanyahu: Hamas Committing 'Double War Crime'; Rails Against 'Mad Islamists'

Israel maintains that the goal of this latest incursion is to destroy Hamas' infrastructure and terrorist tunnels leading into Israel, and says they give neighborhoods ample warning to evacuate. Ashrawi said the numbers of innocent victims are disproportionate because they are trapped.

"These are all human beings and they're being abstracted and they're being anonymously shelled by the strongest army in the region and they are defenseless," Ashrawi said. "They are hemmed in by land, by air, by sea and then if they try to dig tunnels as a way out - what do you expect?"

As Israel intensified its ground operation in Gaza today, Ashrawi said the blame is being misplaced on the civilian population.

"If they respond in any way, they are not only labeled as terror targets, they are dehumanized, they are terrorized, and they're being killed. It's not just adding insult to injury, it's just double and multiple murder. You're maligning a whole nation, and you are giving Israel the time and the means to continue with these massacres and these war crimes. One day they will be held accountable."

When Macdonald asked Ashrawi if Palestinians plan to apply to join the International Criminal Court to bring war crime charges against Israel, she said they plan to take that step, but she'd like to see the situation addressed by the international community before a legal case is prepared.

"I don't believe the world has to wait until we do these things and until we prepare these cases," Ashrawi said. "There has to be immediate intervention to provide the Palestinians with protecting, to curb the Israeli violations and to hold Israel accountable."

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