The report also states that officials have not adequately controlled access to the Plum Island Animal Disease Center.
The document notes that the U.S. Department of Agriculture "permitted eight scientists from other countries access to the biocontainment area without being escorted despite incomplete background checks."
The General Accounting Office report on Plum Island was scheduled to be released Monday. Excerpts were provided Saturday to The Associated Press by a government source on condition of anonymity.
Newsday first reported on it in Saturday's editions.
The newspaper quotes the study as calling security designed to protect against the theft of animal diseases that could be used by terrorists "incomplete and limited."
Among other things, says Newsday, "The report says alarms and door sensors that had been recommended by other security reviews for the biocontainment area 'are not fully operational.' It says there is inadequate lighting outside the research complex for security cameras."
From January to September, congressional investigators examined Plum Island operations, including allegations that replacements for 76 striking maintenance workers were improperly trained.
Critics also have cited the thefts of two laptop computers, accidents involving ferries that bring workers to the island, and power losses.
Sen. Hillary Rodham Clinton and Rep. Timothy Bishop, whose congressional district includes Plum Island, have lobbied for a federal takeover of staffing for the facility. The workers are currently employed by a private contractor.
Neither Clinton nor Bishop returned telephone calls to their offices seeking comment.
Plum Island scientists study contagious animal diseases such as foot-and-mouth disease and swine flu. It is the only facility in the country that has vaccines for those diseases, making it a target for a terrorist attack on the agricultural economy, the report said.
The 850-acre facility was run by the Department of Agriculture until June, when the Department of Homeland Security assumed control of it.
"It is premature for us to comment on the report before we have had an opportunity to review it in detail," said Michelle Petrovich, a spokeswoman for Homeland Security.
Martin Glennon, an attorney for the union representing the striking workers, said the report "confirms everything the union has been saying."