An anti-Syrian politician was killed in Lebanon on Tuesday when a bomb ripped through his car, two days after parliamentary elections brought victory to an alliance opposed to Damascus's role in the country.

George Hawi, a former leader of the Lebanese Communist Party, died instantly in the blast in the Wata Musaitbi neighborhood of Beirut, witnesses and security sources said.

A one-pound charge exploded under the passenger seat of Hawi's Mercedes-Benz and was detonated by remote control, judicial sources said. His driver apparently escaped serious injury.

It was the second killing of an anti-Syrian figure in Beirut this month. Newspaper columnist Samir Kassir was killed on June 2 when a similar explosion destroyed his car outside his home.

The United States said after Kassir was killed that it had information about a Syrian hit list targeting Lebanese leaders. Syrian officials have denied that claim and denounced Hawi's killing.

Secretary of State Condoleezza Rice accused Syria of destabilizing neighboring Lebanon.

"There is a context and an atmosphere of instability. Syria's activities are part of that context and a part of that atmosphere and they need to knock it off," she told reporters as she flew to Brussels on a tour of the Middle East and Europe.

Syria bowed to pressure from within Lebanon and internationally and withdrew its troops from Lebanon in April after the car-bomb assassination of former prime minister Rafiq Hariri in February.

Hawi, 67, did not openly join the anti-Syrian opposition that gained prominence after Hariri's killing but played an important role behind the scenes, bringing together disparate members of the opposition.

Hawi's stepson, also a critic of Syria, blamed remnants of Lebanese security agencies that had been allied with Syrian intelligence, though Lebanon's top security chiefs have resigned in recent months.

"The security agencies continue to kill the democrats and are trying to assassinate democracy in Lebanon and the independence uprising," Rafi Madoyan told reporters. "It is not just George Hawi; there are many others on the hit list."

About 3,000 people held a candlelight vigil for Hawi on Tuesday night, some holding flowers or his picture.

A soldier guards the site of the second car-bomb killing of an anti-Syrian figure this month.Relatives cry at the scene of a car bombing that killed anti-Syrian politician George Hawi, a former Communist Party leader.