BEIRUT -

The din of construction roars over Beirut's traffic as skyscrapers race toward completion. A warm autumn sun beats down on shoppers browsing through Beirut Souks, the luxury retail shopping complex built on a former battleground of Lebanon's 15-year civil war. Latte drinkers plug headphones into shiny new laptops at a seafront Starbucks, tuning out warnings that this place is about to explode.

Politicians and a parade of diplomats have voiced concern in recent days that indictments to be issued soon by a U.N. tribunal investigating the 2005 murder of Lebanese Prime Minister Rafik Hariri will usher in a new era of political instability, or even bloodshed, should the Lebanese Shiite militia Hezbollah be fingered in the killing.

"People are more worried than ever,'' said one high-ranking government official who declined to be identified by name. "I tell my employees I don't expect street violence, but I have the impression they don't believe me.''

While Lebanese continue with their daily routines, some are securing second passports or visas in case their country - once again - spirals out of control.

"I would like them to have a second option if something happens,'' said Rita Massaad, a Lebanese notary who has been trying to secure Greek passports for her children. Her only hope is that her fiancÃ©, a Lebanese lawyer, has one Greek grandmother.

"Living in Beirut is like living on a volcano,'' Massaad said. "You never know when it's going to blow. You can have the most beautiful life ever and then lose everything in 24 hours.''

The stakes are also high for the United States, which has watched its pro-Western allies - swept to power five years ago after Hariri's assassination by a car bomb - wither while Hezbollah, backed by Iran and Syria, has grown in strength.

The last thing the United States wants now is a new Sunni-Shiite battle front as it struggles to contain similar sectarian tensions in Iraq, observers here say. Israel also is watching events anxiously, concerned that any internal Lebanese squabbles could spill southward and spark a renewed confrontation with Hezbollah, with which the Israeli military waged a deadly war to an inconclusive end in 2006.

Recent reaction to reports that Hezbollah members could be named in Hariri's killing has demonstrated just how much power the organization has over the country's affairs - and its psyche.

In a blustery televised speech Thursday night, Hezbollah chief Hassan Nasrallah said he won't allow any members of his group to be arrested. "Any hand that will touch any of them will be cut off,'' Nasrallah told a cheering crowd in Beirut's southern suburbs, Hezbollah's stronghold.

Observers here say if Hezbollah were named as being behind the murder of a Sunni leader, it would fuel historic Sunni-Shiite tensions that date back 1,400 years.

Hezbollah is a powerful member of Lebanon's unwieldy governing coalition that was nudged together by outside powers including Qatar and Saudi Arabia in an effort to maintain domestic stability. It also is considered a terrorist group by the United States and Israel.

Hezbollah tried to pressure Prime Minister Saad Hariri, 40, the son of the assassinated prime minister, to withdraw his support for the United Nations-led tribunal. It tried to delegitimize the tribunal for not looking into the possibility that Israel could have been behind the killing, a claim Israel denies. Late last month, two tribunal investigators were beaten as they arrived to do interviews in Beirut's southern suburbs, embarrassing the Lebanese government.

Most recently, on Wednesday, Hezbollah tried and failed to force the cabinet to vote to send people who allegedly gave false testimony to investigators to be tried in Lebanon's top court. Hezbollah hopes such a move will delay the release of the indictments. Hariri and his allies blocked the vote temporarily, leaving the cabinet in political deadlock.

"The future of this country is depending on the tribunal,'' said Antoine Andraus, deputy head of Hariri's Future Movement political party.

Walid Jumblatt, the former Druze warlord and key Lebanese political figure, regrets originally championing the tribunal. "We have created a time bomb, a deadly time bomb,'' Jumblatt said.

The United States has remained unwavering in its political and financial support for the tribunal, seeing accountability as key to transforming Lebanon into a sovereign entity, free of political violence - a message that John F. Kerry (D-Mass.), chairman of the Senate Foreign Relations Committee, carried to Beirut and Damascus last week.

"I emphasized this is not a United States event, and it's not a Hariri event. It's an international commitment to try to end the era of assassinations in Lebanon,'' Kerry said by telephone from Damascus.

Still, all of this talk about assassination and justice hasn't yet blistered the Lebanon that's booming. In addition to the construction craze, tourism is up and total assets of Lebanese banks grew by 10 percent in the first nine months of this year, showing that people aren't afraid to keep their money where it is.

"We're pretty confident, and I think the person on the street has a confidence in the system,'' said Mohamed Ali Beyhum, executive general manager of the Lebanese bank, BankMed.

"We cannot allow ourselves to be distracted by threats,'' he added. "We have to go on doing our business regardless."