It looks like army officials have suspended most research involving dangerous germs at the biodefense laboratory at Fort Detrick, Md., which the FBI linked to the anthrax attacks of 2001. They discovered that some pathogens stored there were not listed in a laboratory database. The suspension started on Friday and could last for at least three months.

Its main purpose is to allow a complete inventory of hazardous bacteria, viruses and toxins stored in refrigerators, freezers and cabinets in the facility, the Army Medical Research Institute of Infectious Diseases. Col. John P. Skvorak ordered the inventory, as he is the institute’s commander. According to him, it’s most likely that some germs and toxins in storage were not in the database.

After the 2001 anthrax letters, which killed 5 people, rules for keeping track of pathogens were tightened. However, pressure to improve recordkeeping and security at the Army Institute intensified six months ago, after the suicide of Bruce Ivins. Prosecutors had been preparing to charge Dr. Ivins with making the deadly anthrax powder in his laboratory there.

This suspension will most likely interrupt dozens of research projects at the institute, whose task is to develop vaccines, drugs and other measures to protect American troops from germ attacks and disease outbreaks. Anyway, it looks like some critical experiments involving animals will not be halted.

The anthrax case in 2001 has underscored the threat of biological attack by biodefense insiders like Dr. Ivins, who have access to pathogens and the expertise to work with them. The number of such researchers has grown rapidly since 2001, as the anthrax attacks led to a rapid addition of laboratories working on potential bioweapons.