Representatives of New York's police and fire departments will ring the opening bell of the New York Stock Exchange on Monday, ending a four-day shutdown forced by devastating terror attacks that tore through lower Manhattan's financial district.

In honor of the victims and their families, two minutes of silence will follow the traditional opening bell, a NYSE spokeswoman told Reuters on Sunday. NYSE, the world's largest stock market, is located three blocks southeast of the mountain of rubble that used to be the World Trade Center.

"All the testing is completed and everything is a go," a NYSE spokesperson said. "Everything was completed yesterday."

Investors are bracing for a rocky start. The outlook for stock prices, at least in the short term, is grim, analysts say.

Despite the prospect of a sharp decline in share prices on Monday morning, officials have been determined to reopen the stock markets on Monday, in part because of the symbolism of a speedy return to normalcy.

The task has been formidable. U.S. financial markets have been paralyzed since two hijacked planes toppled the World Trade Center's twin 110-story towers on Tuesday, leaving an enormous pile of twisted steel and glass and some 5,000 people feared dead. It has been the longest shutdown since March 1933, when President Franklin Delano Roosevelt ordered a special banking holiday to prevent bank runs in the Great Depression.

"We think we're ready for it," Mayor Rudolph Giuliani said Sunday. "Some of it obviously ... is trial and error."

On Sunday, the acrid smell of dust and debris still hung in the air of the financial district. The loud whirring of generators brought in to replace the disrupted main power supply contributed to the sense of disaster permeating the area.

"It's still kind of dark and dreary ... and smells a little funky, it's kind of dusty," one NYSE spokeswoman said. "The rain must have cleared a lot up. But it's still dusty."

An army of street sweepers, many on ladders armed with hoses and brooms, were racing against time to spruce up the financial district as National Guardsmen patrolled the area in Hummer vehicles. An enormous American flag hangs from the front of the NYSE building, Wall Street's most famous landmark.

Delis and other eateries slowly were opening up on Sunday afternoon. Wall Street's tenants were taking a peek at their operations and preparing for Monday.

"People are staying in hotels and sleeping in the building; we're just trying to get our building back on line in time for Monday and take it from there I guess," a local businessman said. "We're working 'round the clock, everyone's doing all they can."

Other Exchanges Also Ready for Business

The two other main U.S. exchanges, the American Stock Exchange and the Nasdaq, also will reopen after successful weekend tests. The Nasdaq's systems are up and running, a spokesman told Reuters on Sunday. The most critical tests checked on the market's connectivity via telephone lines to Wall Street's scattered brokerage firms.

The American Stock Exchange will resume stock trading on the NYSE and options trading on the Philadelphia Stock Exchange. The Amex said its building, which is located just a block south of where the World Trade Center stood, suffered no structural damage. But the exchange decided against trading on its own premises due to "significant utility, access and safety issues and the need to complete building maintenance."

The Securities and Exchange Commission said on Sunday that all the nation's securities markets would open on Monday.

"The Commission is satisfied with the conclusions reached by the stock exchanges and the Nasdaq, and will continue to monitor the systems when trading resumes," the SEC said.

Instinet Group Inc., which operates the No. 1 U.S. alternative stock trading system and is majority owned by news and financial data group Reuters Group, will begin trade of Nasdaq stocks at 8 a.m. EDT and NYSE stocks at 9.30 a.m., said spokesman Calvin Mitchell.

Pictures Silently Mark the Missing

On the edge of the district at the Mt. Sinai Medical Center on Gold Street, the windows of the emergency department are plastered with pictures of people missing in the attacks. Many worked for financial services firms, which suffered the biggest losses in the attacks.

Most of the pictures carry short descriptions of the missing, such as what they were wearing last Tuesday and their distinguishing marks. Some lampposts also were plastered with similar pictures of the missing.

Around the South Street Seaport area, restaurants that would normally be packed on a sunny day in mid-September remained closed. On the tables outside one Mexican restaurant the only activity came from two policemen smoking cigarettes.

The NYSE was undamaged, but battered brokerage operations, crippled communications and lack of access to lower Manhattan — which has been cordoned off since the devastating attack — had thwarted Wall Street's efforts to recover. Nearly $43 billion worth of stocks change hands on the exchange each day.

Since the attack, the NYSE, Nasdaq, Wall Street firms, the city and state joined with telecommunications and power providers Verizon Communications and Consolidated Edison Inc. to make repairs necessary for resumption of trade.

Verizon said Sunday its communications network, damaged in the World Trade Center attacks, passed service tests with the NYSE and appeared ready for stocks to resume trading Monday.

Off to a Rocky Start

The attacks on the U.S. have worsened fears a sluggish U.S. economy will slip into a recession. Among the latest grim news: Continental Airlines Inc. said it was laying off 12,000 staffers and warned it could file for bankruptcy.

Most pundits expect stocks prices to sag at the opening at 9.30 a.m. EDT. Prospects darkened after European stocks on Friday plunged more than 5 percent to near three-year lows on fears of increased violence.

"People are going to wonder how this attack is going to affect all [their] companies," said Matthew Norris, a portfolio manager with Advantus Capital Management in Minneapolis. "They'll take money out and think awhile before putting it back in. I'm not that optimistic in the short term."

On the plus side: The Federal Reserve may cut interest rates to prevent a possible recession and has injected money into the system; regulators have relaxed rules on corporate share buybacks and some companies already have announced repurchases; and a grassroots movement has sprung up on the Web to urge Americans to buy stock as their patriotic duty.

U.S. Vice President Dick Cheney sounded a note for cautious optimism on Sunday when he said the U.S. economy was "strong" and, while the country "quite possibly" could be in recession, he expected it to rebound later this year.

Reuters and The Associated Press contributed to this report.