WASHINGTON (AFP) - US government attorneys on Tuesday begin what is expected to be a drawn-out courtroom battle, trying to squeeze 280 billion dollars from big tobacco companies which federal authorities say used fraud to amass staggering profits.

The government charges the tobacco industry manipulated nicotine levels to increase addiction, targeted teens with multibillion-dollar ad campaigns, sold low-tar cigarettes as healthier knowing they were not, lied about smoking hazards and manipulated or hid research to the contrary.

Much of the government's case, which took five years to reach trial, is based on charging the industry with violating the Racketeer Influenced and Corrupt Organizations (RICO) act, a federal statute designed to counter Mafia infiltration of business.

The cigarette companies "have engaged in and executed -- and continue to engage in and execute -- a massive 50-year scheme to defraud the public," according to the government's court filing.

The scheme resulted "in extraordinary profits for the past half-century but has had devastating consequences for the public's health."

In 1953, bosses of the five leading US cigarette manufacturers met at the Plaza Hotel in New York and hatched a plan "to jointly conduct a long-term public relations campaign to counter the growing evidence linking smoking as a cause of serious diseases," the documents read.

The result was a "fraudulent scheme" in which the industry questioned the mounting evidence against smoking and sponsored its own "independent" research, all aimed at reassuring the public and denying the harm of smoking, the documents say.

Government lawyers also want tough controls on cigarette manufacturing, marketing, labeling and sales.

Defendants include Philip Morris USA -- which controls about half of the US tobacco market -- RJ Reynolds Tobacco, Loews Corp's Lorillard Tobacco, British American Tobacco PLC unit Brown and Williamson and the Vector Group's Liggett Group.

The use of the RICO act "should be your first indication of how big a stretch the government's claim is here," said William Ohlemeyer, the in-house attorney for Altria, the parent company of Philip Morris.

The tobacco companies "sell a dangerous and addictive product, but it is sold with a health warning," he said. Much of what the Department of Justice attorneys will claim is fraud "are actually constitutionally protected activities that are not unlawful, let alone fraudulent," he said.

Ohlemeyer insisted the industry has already met many of the government demands in a landmark 1998 lawsuit with 46 state governments over ballooning state health care costs.

At the time, the four top tobacco companies agreed to pay the states 206 billion dollars over 25 years, funded largely by a cigarette price hike.

In the trial, which opens September 21, some 73,000 trial exhibits have been listed and both sides will present 300 witnesses. Each side has 12 weeks to present its case, Justice Department officials said in a background briefing.

The trial will be held four days a week, five hours each day, with little time off for the end-of-year holidays. Barring disruptions, the presentation phase alone will end in March 2005.

The government has a team of 35 attorneys and 16 assistants working on the case led by Sharon Eubanks, a 21-year Justice Department veteran. Since 1999, the government litigation team has spent more than 135 million dollars on the case.

Defense attorney Dan Webb -- dubbed a "superlawyer" by The New York Times -- will represent Philip Morris and coordinate with an army of lawyers from the defendants.

Webb, 58, is the country's top white-collar criminal defense attorney, according to a survey of lawyers by the Corporate Crime Reporter newsletter.

Many observers believed the government lawsuit, filed in 1999, when Democrat Bill Clinton was president, would be dropped by Republican George W. Bush.

The tobacco industry is known to contribute heavily to the Republican Party -- Bush's own political guru, Karl Rove, even served as a Philip Morris consultant in the 1990s.

But the case survived both Judge Gladys Kessler's dismissal of a government claim for medical cost recovery in 2000 and attempts to reach a negotiated agreement in mid-2001.