A British medical journal said Friday that it had given U.S. regulators confidential drug company documents suggesting a link between the popular anti-depressant Prozac (search) and a heightened risk of suicide attempts and violence.

The British Medical Journal reported in its Jan. 1 issue that documents it had received from an anonymous source indicated that Prozac's manufacturer, Eli Lilly & Co. (search), was aware in the 1980s that the drug could have potentially troubling side-effects.

The journal said the documents, reportedly missing for a decade, had formed part of a 1994 lawsuit against Eli Lilly on behalf of victims of a workplace shooting in Louisville, Ky. The gunman who killed eight people and himself in 1989, Joseph Wesbecker, had been prescribed Prozac a month before the shootings.

Eli Lilly won the case but later disclosed it had settled with the plaintiffs during the trial.

The journal said one of the records, dated November 1988, reported that fluoxetine (search), the generic name for Prozac, had caused "behavioral disturbances" in clinical trials.

The journal said it had turned the documents over to the U.S. Food and Drug Administration, which had agreed to review them.

The journal said the office of Congressman Maurice Hinchey, D-N.Y., also was examining the documents to determine whether Eli Lilly had withheld data from the public and the FDA.

"This is an alarming study that should have been shared with the public and the FDA from the get-go, not 16 years later," Hinchey was quoted as saying.

In a statement to the journal, Eli Lilly said Prozac "has helped to significantly improve millions of lives."

"It is one of the most studied drugs in the history of medicine and has been prescribed for more than 50 million people worldwide. The safety and efficacy of Prozac is well studied, well documented and well established."

In October, FDA ordered that all antidepressants carry warnings that they "increase the risk of suicidal thinking and behavior" in children.