Amir al-Far, 16, from the Askar refugee camp in Nablus on the West Bank, blew himself up and killed three other people in an open-air food market in the heart of Israel's capital. Thirty-five other people were injured.
The military wing of the Popular Front for the Liberation of Palestine (PFLP) named al-Far as its "martyr", making him the youngest bomber since the September 2000 outbreak of the Palestinian uprising.
"My son was very young, he was just a child. Why did they choose him?" cried a distraught Samira Abd Allah, the 45-year-old mother.
"I don't believe it, I haven't been properly informed.
"But if it's true, Amir was only a child. He was born on 6 June, 1988 and was only 16 years and four months old. They could have spared him from this," she said.
"Why didn't they send someone older? We are all ready to sacrifice ourselves for the motherland, but my son was little, he was just a baby," the mother sobbed.
The boy had for the past week kissed her hand and forehead every day and asked her to pray for him. "I thought it was because of the influence of the [Muslim] holy month of Ramadan," she said.
Four people died in the bombing
Amir left home at 7.30am (0530 GMT) on Monday without saying where he was going, said brother Umar, adding he was still not sure whether to believe the PFLP's claim despite a photograph it produced showing Amir armed with a machine gun.
Late on Monday, Askar residents were helping the family gather their belongings and evacuate their home before the Israeli army came to carry out its customary destruction of the homes of perpetrators of bomb attacks.
Some residents voiced fears of an Israeli reprisal attack on the refugee camp at large and a possible army operation, as two masked men fired in the air and told local shops to pull down their shutters in mourning.
The bomber's father, Abd al-Rahim al-Far, 54, who walks with a cane due to being shot by Israeli troops in the early days of the intifada said he was shocked that his son would never return.
"I was asleep this morning when Amir woke me up. He kissed me and asked for two shekels (45 cents). He left the house and I went back to sleep," he said.
Palestinian human rights groups have often criticised the recruitment of minors for attacks.