More on the bombing in Jerusalem early today. This one is even more painful to read about than usual because of the number of children killed and injured.

JERUSALEM, Aug. 19 — A Palestinian suicide bomber killed at least 18 people, including children, when he detonated an explosive packed with ball bearings tonight aboard a city bus crowded with families, some of them returning from Judaism's holiest site, the Western Wall.

The blast resounded across Jerusalem as it peeled up the roof of the bus and blew out its windows, smearing human remains on a preceding tour bus and opening a deep wound in the American-backed peace effort.

More than 100 people were reported hurt, many seriously, in one of the deadliest attacks in almost three years of conflict. Men carrying blood-spattered children raced toward approaching ambulances. On a street strewn with broken glass and bloodied sheet metal, a man knelt near the shattered bus to perform mouth-to-mouth resuscitation on a toddler.

Later, in a hospital here, Yaacov Bahar, 35, held his hands in the air in front of him, as though he were still carrying an infant, as he described helping bring four children from the bus. "In my eyes, I'm still seeing the nightmare," said Mr. Bahar, who was being treated for shock. . . .

In Gaza City, the Palestinian prime minister, Mahmoud Abbas, told reporters, "I declare my strong condemnation of this horrible act that doesn't serve the interests of the Palestinian people." Mr. Abbas said he offered "my real sorrow" to the families of the victims.

Israeli officials noted that Israel had recently softened its own demands on the Palestinian leadership, insisting only that it supervise the people Israel considers terrorists and prevent them from committing new attacks, rather than putting them in jail. The bombing tonight appeared certain to renew Israeli and American pressure on Mr. Abbas, to take more forceful action against militant groups. Mr. Abbas said he had ordered his minister of security, Muhammad Dahlan, "to immediately investigate this attack and to take the necessary measures regarding its perpetrators."

Mr. Abbas and Mr. Dahlan have resisted taking action against militants, seeking instead to persuade them to abide by a unilateral suspension of attacks on Israelis declared on June 29. The bombing tonight occurred as Mr. Abbas was meeting in Gaza City with leaders of Islamic Jihad in an attempt to extend the cease-fire, which was to last three months. Mr. Abbas was scheduled to meet on Wednesday with leaders of Hamas, but he canceled that meeting after the bombing. . . .

To call Abbas's meeting with Islamic Jihad at the exact time of the bombing ironic is to stretch the meaning of irony.

Fireworks burst over Hebron tonight as Palestinians there celebrated the bombing. . . .

There were many children aboard the bus this evening, survivors said. Zvi Weiss, 18, a seminary student from Borough Park, Brooklyn, said he was sitting in the second row, squeezed in with three children. One of the children had been left in a vacant seat by his mother, who then pushed the baby carriage toward the back of the bus, he said. "His mother was in the back, so I think — I don't know what to think," Mr. Weiss said. He said he leaped through a window and ran as the explosion enveloped him in "smoke, noise, the smell of fire." He was being treated in Bikur Holim hospital for shrapnel wounds to his arms, which had stained his white shirtsleeves crimson. He was having trouble hearing, a common difficulty of bombing victims.

Yehiya Luria, 38, said the bus was "so full that you couldn't have put a pin in there." He said he was seated at the far back, and also escaped through a window. "There was a lot of blood on me — blood, bits of flesh, teeth, hair," he said. He was being treated for shock. "It was a miracle," he said of his survival. "I prayed at the Western Wall today."

Nearby, a 2-year-old boy lay in another hospital bed, holding a white blanket and a foil bag of snacks as he sucked on a red pacifier and silently watched the bustling ward. His aunt said he had been riding in a sedan that smashed into the back of the bus, and that he was slightly wounded. She said his name was Abraham.

Initial reports by the authorities were that five children were among the dead. The police reported removing 18 bodies from the bus. The bodies and body parts were enclosed in black or white plastic bags, which were placed in a traffic circle among three small trees. Investigators opened the bags to take photographs of the dead to identify them.

Generators hummed as emergency workers in the harsh white glare of portable lamps scoured the red-and-white bus for the remains of the dead. In the shadows, hundreds of young men in the white shirts and broad-brimmed black hats of the devoutly religious gathered on the sidewalks and rooftops, outside a police cordon, to survey the scene.

Three hours after the bombing, a spokeswoman for another hospital, Haddassah Ein-Kerem, said no one had claimed a month-old baby boy brought from the scene, raising the possibility that his parents had been killed.

"He is a very sweet 4-week-old baby boy," the spokeswoman, Yael Bosem-Levy, told Israel Radio. "He has light injuries. He has impact wounds to his stomach, and the entire time he has been here he didn't cry even once."

I find it really difficult to know how to respond to this attack. I could try to say something political, but I really don't know what I would say. To say that one condemns the terrorist murder of children seems so obvious -- but after a while, it is just mere words. Grief is the only first reaction. All I can think of are the children of my friends in Jerusalem, and how I would feel if one of them had been on that bus.

I wrote a poem a while ago that expresses some of the feelings I have each time I hear about such violence. (I know it's risky to present one's own amateur poetry, but please bear with me).

My brother’s blood calls from the ground
and earth will swallow him up.

God called to Cain: Where is Abel your brother?
Cain said to God: your earth will take him,
he is like the rebels who followed Korach;
their fate is to lie in the earth,
buried alive and not dying.
God called to Cain: You are cursed from the ground which gaped open its mouth to take the blood of your brother Abel.
Cain said to God: And your people, O God, your people? They are scattered over the face of the earth and we pursue them to their deaths. Do not speak to me of curses.
God called to Cain: The shedder of human blood, by humans his blood will be shed.
For humans are made in the image of God.
Cain said to God: We have shattered the image like so much broken glass on the city street.

I cradle my brother’s head in my arms
his blood has soaked into the ground and he lies still.
Where is your image O God on this earth?