BEIRUT — An anti-Syrian lawmaker who had just returned to Lebanon two days ago from refuge abroad was killed today along with six other people by a bomb that rocked a Christian neighborhood of the capital, security officials said.

Antoine Ghanem is the eighth prominent anti-Syrian figure to be assassinated since 2005.

The bombing, which the security officials said also wounded 22 people, heightened tensions ahead of a presidential vote that already threatened to throw the country into turmoil.

Many Lebanese fear divisions over the presidency could lead to the creation of two rival governments, a grim reminder of the last two years of the 1975-90 civil war when army units loyal to competing administrations battled it out.

Ghanem, 64, a member of the right-wing Christian Phalange Party, was the target of the bomb, said the officials, speaking on condition of anonymity because they were not authorized to talk to the media.

The Voice of Lebanon radio station, which is owned by the Phalange party, confirmed Ghanem’s death. The identities of the others killed were not immediately known.

The bombing on a main street in the Sin el-Fil district severely damaged nearby buildings and set several cars on fire. Blood and debris covered nearby streets.

The attack came six days before parliament was scheduled to meet to elect a new president in a vote expected to be deeply divisive. Four of the slain lawmakers have been from the American-backed majority coalition, reducing its margin in parliament.

“It is clear lawmakers from the (anti-Syrian) majority are being liquidated,” a Cabinet minister, Ahmed Fatfat, said.

He blamed the Syrian regime for the assassination, adding: “It is the only regime that does not want presidential elections in Lebanon to be held.”

A White House spokeswoman, Dana Perino, said it was “no coincidence” that the attack came as Lebanon prepared to elect a new president.

“Since October 2004, there has been a pattern of political assassinations and attempted assassinations designed to intimidate those working courageously toward a sovereign and democratic Lebanon,” Ms. Perino said.

“The victims of these cowardly attacks have consistently been those who publicly sought to end Syria’s interference in Lebanon’s internal affairs,” she said.

When pressed, Ms. Perino said she was not directly blaming Syria, but added, “As I’ve said, there’s been a pattern, and this would seem to fit into the pattern.”

Syria condemned the attack, which it said was meant to sabotage efforts by the Lebanese people to reach agreement.

“This criminal act aims at undermining efforts made by Syria and others to achieve a Lebanese national accord,” Syria’s state-run news agency SANA quoted an anonymous Syrian official as saying.

A former Lebanese president, Amin Gemayel, who heads the Phalange Party, said Lebanon’s democracy was at stake.

“It’s not anymore a question of presidential elections. It’s a question of the survival of this country and democracy in the country that’s at stake for the time being,” Mr. Gemayel told CNN. The former president’s son, Cabinet minister and lawmaker Pierre Gemayel, was slain in November.

The assassinations of anti-Syrian figures began with a former prime minister, Rafik Hariri, who was killed in a massive car bombing in February 2005. Syria’s opponents in Lebanon have accused Damascus of being behind the killings, a claim Syria denies.

His death sparked massive protests that helped bring an end to Syria’s nearly 30-year domination of Lebanon. Damascus was forced to withdraw its troops from Lebanon in 2005, and a government led by anti-Syrian politicians was elected.