Israeli rescue worker evacuates the wrapped remains of a suicide bomber from the site of the attack in the southern Israeli city of Beersheba

A suicide bomber attacked a bus station in southern Israel Sunday, critically injuring two Israeli security guards. Hours later, Israel approved a border security deal with Egypt to facilitate a complete Israeli pullout from the Gaza Strip.

A Palestinian suicide bomber tried to board a bus at the central station in the southern Israeli city of Beersheba during morning rush hour at the start of the work week. But he aroused the suspicion of the bus driver. Police say security guards chased the bomber, and he blew himself up.

"I saw a terrible ball of fire right in front of my eyes," eyewitness Nissim Vaknin told Israel Radio.

The explosion could have caused mass casualties, had the bomber succeeded in boarding the bus.

The attack came less than a week after Israel completed its evacuation of Jewish settlers from the Gaza Strip.

"It's very troubling. We take down 21 settlements in Gaza, and it appears that terrorism is the response," said Israeli spokesman Mark Regev.

Palestinian militant groups had promised revenge, after Israeli troops raided a West Bank refugee camp last week, and killed five wanted gunmen.

Palestinian leader Mahmoud Abbas described that raid as a "provocation." But he also denounced the Beersheba bombing as a "terrorist attack," and urged his people to abide by the six-month-old cease-fire.

Hours after the bombing, the Israeli cabinet approved the deployment of 750 Egyptian troops on the Gaza border to prevent weapons-smuggling to Palestinian militants. The deal will enable Israel to withdraw all its troops from Gaza.

But Israeli hawks doubt that Egypt will deliver the goods. Parliamentarian Ehud Yatom says, if Israel withdraws from the border, Gaza will become an arsenal for terrorists.

"I think that it's very, very bad decision, very, very big mistake," he said.

Prime Minister Ariel Sharon wants to withdraw to the international border, so Palestinians won't have an excuse for continuing attacks against Israel.