Erez Crossing, Gaza Strip - A 22-year-old mother-of-two told of her love for her children and then set off a bomb meant to turn her into "deadly shrapnel".

The Palestinian mother became the first Hamas woman suicide bomber on Wednesday when she blew herself up at the main border crossing between Israel and the Gaza Strip, killing four Israelis.

The four included soldiers and at least one civilian, the army said. Four Palestinians were among the seven wounded.

In a videotape left behind, Reem Al-Reyashi smiled as she cradled an assault rifle.

"I always wanted to be the first woman to carry out a martyrdom operation, where parts of my body can fly all over," she said in a farewell message taped by the group."

"That is the only wish I can ask of God."

Wearing a green Hamas sash and headband, Reyashi, from a middle-class merchant family in Gaza, said she had dreamed since she was 13 of becoming a martyr.

She glanced occasionally at a rocket-propelled grenade launcher lying on a table in front of her.

Behind her, two green flags bore the central creed of Islam: "There is no other God but Allah, and Mohammed is his messenger".

Reyashi professed her love for her children - a three-year-old boy and an 18-month-old girl - before an attack that she said was meant to turn her body into "deadly shrapnel".

She concluded by saying: "God gave me two children and I loved them so much. Only God knew how much I loved them."

The Hamas militant blew herself up in a terminal where Palestinian labourers from the fenced-in Gaza Strip were being put through Israeli security checks before entering a nearby industrial complex.

"Glass and black smoke flew everywhere. Arabs were screaming, Jews were screaming," said a Palestinian witness, her clothes stained with the blood of others.

Witnesses said the bomber was faking a limp when she set off a metal detector operated by Israeli security personnel at Erez.

Moments before, a Palestinian woman labourer standing in the queue had offered Reyashi a helping hand.

"She looked at her, she thanked her and told her to back off," one witness said.

Israeli Brigadier-General Gadi Shamni said: "She managed to hoodwink the soldiers by saying she had a metal surgical implant.

"A female soldier was sent for to search her. She used this opportunity to enter the building... and blow up."

The militant Islamic group Hamas and the al-Aqsa Martyrs Brigades claimed joint responsibility for the suicide bombing, which they said was to avenge Israel's killing of Palestinians. They vowed to escalate attacks.

It was the first suicide attack since a December 25 bombing killed four Israelis near Tel Aviv.

Israel has often responded to such attacks with missile strikes. For now, its only move was to close the industrial zone for the next few days, idling 3 000 Palestinian labourers.

Hamas, the main group behind a campaign of suicide bombings, said it sent a woman for the first time because of Israeli security "obstacles" facing its male bombers. Smaller militant groups have already deployed female bombers.

"Resistance will escalate against this enemy until they leave our land," Hamas founder Sheik Ahmed Yassin said in Gaza.

Palestinian Prime Minister Ahmed Korei did not immediately condemn the bombing, as he has after attacks in Israel.

Instead he said Israel's military crackdown "does not help to achieve quiet" and called for a mutual ceasefire. - Reuters