BRAZEN: The Eli Lilly pharmaceutical warehouse in Enfield, Connecticut, where authorities say tens of millions of dollars worth of prescription drugs have been stolen in a brazen, well-planned heist.

In a Hollywood-style heist, thieves cut a hole in the roof of a warehouse, rappelled inside and scored one of the biggest hauls of its kind - not diamonds, gold bullion or Old World art, but about US$75 million (NZ$105 million) in antidepressants and other prescription drugs.

The pills - stolen from the pharmaceutical giant Eli Lilly & Co in quantities big enough to fill a tractor-trailer - are believed to be destined for the black market, perhaps overseas.

"This is like the Brink's pill heist," said Erik Gordon, a University of Michigan business professor who studies the health care industry. "This one will enter the folklore."

The thieves apparently scaled the brick exterior of the warehouse in an industrial park in Enfield, a town about midway between Hartford and Springfield, Massachusetts, during a blustery rainstorm before daybreak Sunday. After lowering themselves to the floor, they disabled the alarms and spent at least an hour loading pallets of drugs into a vehicle at the loading dock, authorities said.

"Just by the way it occurred, it appears that there were several individuals involved and that it was a very well planned-out and orchestrated operation," Enfield Police Chief Carl Sferrazza said. "It's not your run-of-the-mill home burglary, that's for sure."

Experts described it as one of the biggest pharmaceutical heists in history.

Edward Sagebiel, a spokesman for Indianapolis-based Eli Lilly, put the wholesale value of the drugs at US$75 million and said they included the antidepressants Prozac and Cymbalta and the anti-psychotic Zyprexa. No narcotics or other painkillers were in the warehouse, he said.

Other pharmaceutical warehouses have been hit with similar burglaries in recent years, but experts said the value of the Eli Lilly heist far eclipses any other prescription-drug thefts they have tracked. The thieves could easily net US$20 million to US$25 million, Gordon said.

Enfield police would not say whether the building had surveillance video or whether employees are being investigated. The building is unmarked and unprotected by fences.

The FBI was called in.

Experts said the heist shared many traits with warehouse thefts of pharmaceuticals last year near Richmond, Va., Memphis, Tennessee, and Olive Branch, Miss. Those thieves also cut through ceilings and sometimes used trapeze-style rigging to get inside and disable the main and backup alarms. In some cases, they sprayed dark paint on the lenses of security cameras; in others, they stole disks in the security recording devices.

Enfield police and the FBI would not comment on whether some of those techniques were also used in the Eli Lilly theft.

"The level of sophistication in these thefts is very high," said Dan Burges, director of intelligence at FreightWatch International, a Texas-based security company. "These thieves actively target certain products. They find out where they are, they go there, they come looking for it. They probably were conducting surveillance on that warehouse for days, if not weeks, before that theft occurred."

Burges and Gordon said the thieves probably already had a buyer lined up, possibly an online pharmacy or someone in South America or Asia, where drug regulations are lax. Gordon said it is unlikely the drugs would end up at a local hospital or drugstore chain.

"The people with a reputation to protect, a CVS or a Target or a Kroger or most hospitals, they don't want to take any chances," he said. "It's too big a risk. You're talking about people's health."

However, stolen drugs have made it into the US health care system, often through Internet suppliers or crooked wholesalers.

Last June, thieves stole 129,000 vials of insulin in North Carolina. The drugs were not properly refrigerated, and later surfaced at a medical centre in Houston. The Food and Drug Administration said in August that some patients suffered unsafe blood sugar levels after using them and that it had recovered just 2 percent of the stolen insulin.

"We know that any number of unscrupulous people interested in profit find ways to convince some secondary wholesalers to put these products back into circulation and on into pharmacies," FDA spokesman Tom Gasparoli said in a statement.

Pharmaceuticals made up 5 percent of the thefts of commodities in 2009 in the US The average such heist was worth about US$2.5 million, according to FreightWatch. Pharmaceuticals are usually stolen from trucks or cargo containers - there were a few dozen such thefts last year - though Burges said warehouse break-ins are on the rise as thieves become more sophisticated.

"They're very creative, they're very good at what they do, and catching them is a very difficult thing," he said.

Zyprexa and Cymbalta were Eli Lilly's two best-selling drugs last year. Prozac was Lilly's first billion-dollar drug and the company's top seller before it lost patent protection several years ago. The thefts will not cause any national shortages of the products, Sagebiel said.