Students and members of the emergency services have been describing horrific scenes that followed an attack by a gunman at a Jerusalem seminary.
Medics say they faced shocking scenes as they entered the building
One medic arrived at the scene as gunfire was still being exchanged.
"The terrorist was shooting at us. We all hide under the cars, under the buses that were here.
"When we got in after the police guys sterilised the place, there was a terrible scene.
"We saw young guys, 15-, 16-year-old guys lying on the floor with their Bibles in their hands, all dead on the floor because the terrorist guys went inside the place and killed those eight or nine young guys who were only here learning in Jerusalem."
Yehuda Meshi Zahav, head of the Zaka rescue service, entered the library after the attack.
"The whole building looked like a slaughterhouse," he told the Associated Press news agency. "The floor was covered in blood. The students were in class at the time of the attack.
"The floors are littered with holy books covered in blood."
Students are reported to have jumped out of the building as the gunman opened fire.
One of the students, Yitzhak Dadon, said the attacker was wearing torn jeans and fired at the students with a Kalashnikov assault rifle. Mr Dadon said he shot the attacker twice in the head, wounding him.
"I laid on the roof of the study hall, cocked my gun and waited for him. He came out of the library spraying automatic fire," he said.
"I shot him twice in the head. He started to sway and then someone else with a rifle fired at him, and he died."