When Israel conducted its deadliest raid in the occupied West Bank in almost two decades this week, a young Palestinian nurse rushed to help.

As critical case after critical case succumbed to their wounds, Elias al-Ashqar, 25, let out a blood-curdling roar.

"My father! My father," he screamed, as he realised his dad was among the 11 people killed in the raid on the flashpoint city of Nablus.

"I was on my regular shift in the hospital on Wednesday morning. I was busy with a group of medical students from An-Najah University," Ashqar told AFP.

It was then that the emergency department alarm bell sounded, warning of multiple incoming casualties, an increasingly frequent occurrence amid the growing violence of recent months.

As he entered, he saw two people on opposite beds. "The doctors were trying to resuscitate them," he told AFP, tears welling in his eyes.

"I helped the doctors with the first patient. He was young but soon died, so I tried to help save the life of the second man without looking at his face.

"The doctors were trying to resuscitate him, so I left them to help other cases... but I had a strange feeling the second wounded man belonged to me.

"I ran back and asked about him, and they told me that he had been martyred, so I subconsciously pulled back the curtain, and discovered that the martyr was my father."

Ashqar said his father Abdel Aziz, 65, had been returning from prayers in the Old City when he was caught up in the Israeli incursion. He said his father was unarmed.

Recent clashes in Nablus are at least partly the result of the emergence of a new militant group in the city dubbed the Lions' Den, that claims to rise above traditional factional loyalties and has been blamed for a number of attacks on Israeli targets.

Israel said Wednesday's raid targeted two Lions' Den members, as well as a member of the Islamic Jihad militant group.

As young men lined up to offer their condolences on Friday, Ashqar said his father had simply been going about his everyday life and lamented the prospects of ever winning justice for him.

"I don't know whether the Palestinian person is different to the European or American person," he said.

"We just wish we could have a life, we just want a life."