A suicide bomber blew himself up near a bus station in the southern Israeli city of Be'er Sheva early Sunday, wounding at least 21 people.

This was the first such attack since Israel completed its withdrawal from the Gaza Strip and part of northern West Bank last Tuesday.

The bomber had aroused suspicion of the driver of a crowded No. 9 bus. The driver alerted security guards, who pursued the attacker until he set off the bomb.

Witnesses said the alertness of the driver and the guards prevented what could have been a much more costly attack. The explosion occurred during the morning rush hour at the start of the Israeli work week.

The bus driver told Israel Radio the suicide bomber was carrying a heavy bag and drew his suspicion.

"I was suspicious of him, he had a large back pack and a plastic bag in his hand," Rami said. "I pointed him out to the guard. He was about 20 meters from the bus when he blew up. It was a huge The bomber detonated the explosives, seriously wounding the two guards. Yehuda Shoshan, a paramedic, said the two security guards were critically wounded. "They were suffering from shrapnel wounds and burns all over their bodies," he told TV Channel 10.

Since Sunday was always a high-traffic day in the country's bus stations, with crowds of soldiers returning to their army bases, the security guards effectively prevented the attack that could have caused multiple fatalities.

Roadblocks were set up in the surrounding area immediately after the bombing to capture the drivers who may have transported the bomber to the site.

Most of police officers who would usually be on duty Sunday morning were on vacation after their intensive work to evacuate settlers from the Gaza Strip and part of northern West Bank, Channel 10 said.

There was no immediate claim of responsibility for the blast so far.

David Baker, an official of Israeli Prime Minister Ariel Sharon's Office, said, "Israel has done its part in advancing the peace process, but the Palestinian (National) Authority has not taken the necessary steps to stop attacks.

"Without other such steps there will be no progress between the sides," Baker said.

For his part, chief Palestinian negotiator Saeb Erekat said, "We condemn this attack and call upon all to make a maximum effort in order to maintain the truce and quiet."

"Violence will bring more violence, and what Israelis and Palestinians need today is more peace and not violence," he said.

Hours before the bombing, Palestinian leader Mahmoud Abbas told Israel Radio in an interview that a ceasefire reached with Israel in February will be upheld.

"Contrary to statements made earlier by Hamas, the Hudna (ceasefire) will not end in 2005 but will be upheld indefinitely," said Abbas.

A suicide bomber last struck Israel on July 12, killing five people outside a shopping mall in the coastal city of Netanya.

(Xinhua News Agency August 29, 2005)