Last month’s alleged chemical attack near Damascus has refocused attention on Syria’s 30-year-old biological weapons research.

Syria’s bioweapons program, which U.S. officials believe has been largely dormant since the 1980s, is likely to possess the key ingredients for a weapon, including a collection of lethal bacteria and viruses as well as the modern equipment needed to covert them into deadly powders and aerosols, according to U.S. and Middle Eastern officials and weapons experts.

This latent capability has begun to worry some of Syria’s neighbors, especially after allegations that the regime of President Bashar Assad used internationally banned chemical weapons against civilians in an Aug 21 attack.

Top intelligence officials in two Middle East countries said they have examined the potential for bioweapons use by Syria.

BIOWEAPONS AS RETALIATION

Although dwarfed by the country’s larger and better-known chemical weapons program, Syria’s bioweapons capability could offer the Assad regime a way to retaliate because the weapons are designed to spread easily and leave few clues about their origins, the officials said.

“We are worried about sarin, but Syria also has biological weapons, and compared to those, sarin is nothing,” said a senior Middle Eastern official, who like several others interviewed for this report agreed to discuss intelligence assessments on the condition that his name and nationality not be revealed. “We know it, and others in the region know it. The Americans certainly know it.”

U.S. officials acknowledge the possibility of a latent bioweapons capability but are divided about whether Syria is capable of a sophisticated attack.

Historically, more than a dozen countries have manufactured biological weapons, including the United States, Britain and Russia, all of which abandoned their programs. Syria is one of the few countries that Western intelligence agencies suspect continued some research.

Syria appeared to publicly acknowledge its biological weapons capability in an unusual statement in July 2012 by the country’s Foreign Ministry spokesman, Jihad Makdissi. Responding to Western reports about Syria’s chemical weapons stocks, Makdissi said in a televised interview that Syria would never use “any chemical and biological weapons … inside Syria.”

He said the Syrian military was safeguarding “all stocks of these weapons.”

AN ADMISSION AND A DENIAL

It was the first direct acknowledgment by Syria that such stockpiles might exist, and Makdissi’s voluntary mention of biological weapons took many analysts by surprise. Shortly afterward, the spokesman retracted his remarks in a statement posted on Twitter, saying Syria had no chemical or biological weapons of any kind.

But other governments, including the United States, have long believed that Syria had developed at least a rudimentary biological weapons capability along with its massive stockpile of chemical munitions.

A report prepared for Congress this year by the Office of the Director of National Intelligence concluded that Syria possesses a “longstanding biological weapons program,” adding that parts of the program “may have advanced beyond the research and development stage, and may be capable of limited agent production.”

Other intelligence assessments have been more cautious, citing a lack of hard evidence that Syria’s fledging efforts progressed to “weaponizing” pathogens for use in military rockets and shells. But some officials and independent experts say military biological weapons are not needed to launch a bioterrorist attack on civilian populations.

“We know that they went at least as far as research and development,” Rep. Mike Rogers, R-Mich., chairman of the Permanent Select Committee on Intelligence, said in an interview. “That means they’re far enough along to have capabilities.”