Houston (Texas): The downtown Houston headquarters of collapsed energy titan Enron evoke an old West ghost town. Entire floors of the once bustling mirrored-glass building are practically deserted, divisions wiped clean and thousands of former employees absent from the desks they once occupied.

Inside the company's 50-story tower, the memory of the largest corporate failure in US history looms large, like the silver Enron logo outside the main entrance that once reached for the sky and is now just seen as crooked.

Once the United States' seventh-largest company, Enron is now the target of a series of government investigations and is struggling to salvage whatever it can, as its subsidiaries are sold off one by one and some 4,500 of its 7,000 employees seek other work.

From time to time, remaining employees emerge from the Smith Street building, alone or in groups, to smoke cigarettes in a park across the street.

Morale here has hit an all-time low.

"There is not much of an ambiance," confides a computer technician, speaking on condition of anonymity. "It looks like a funeral home. It's actually pretty depressing."

"Some floors are completely deserted," he adds. "On mine, there must be 50 people left, instead of maybe 300 before."

Across the street, a new $ 200 million high-rise, which Enron built to unclutter its crowded headquarters, stands vacant.

Just a short while ago, the streets here were lively and teeming with people. Enron was one of Wall Street's darlings, its stock a hot seller and confidence in the firm unwavering.

Now, in the Enron building's lobby, the television screens that once displayed financial news have been switched off and security guards stand watch to make sure no undesirable visitors get past their post.

The Federal Bureau of Investigation (FBI) agents and Securities and Exchange Commission investigators who came to the building three weeks ago are long gone, as are the trucks from various television stations that were camped outside the building day and night after the firm filed for Chapter 11 bankruptcy protection on December 2.

Several police cars still guard the entrance to the building.

Inside, though, it is mostly business as usual for the bank, coffee shop and athletic centre though the monthly fee has jumped from $ 10 to $ 25.