The world must face the inevitability of a bio-terror attack by al-Qaeda, the head of Interpol has warned.
Interpol says emergency services are not prepared for attack
Police and health authorities around the world were underprepared for such an attack, Ron Noble told a bio-terror conference in Cape Town, South Africa.
An attack could see smallpox, anthrax, botulism or Ebola-style viruses released into Western cities.
The Cape Town event is the first of three sessions to train medics and police how to deal with attacks.
Further sessions will be held in Chile and Singapore during 2006.
Patient but deadly
Addressing delegates from 41 African nations, Mr Noble said al-Qaeda's track record of deadly, unexpected terror attacks put the threat into focus.
Evidence collected from sympathetic websites also pointed to an avowed intention to stage bio-terror attacks if operatives gained the capability, he added.
"Al-Qaeda has openly claimed the right to kill four million people using biological and chemical weapons," he said.
"Al-Qaeda is willing, able and patient enough to plan and prepare to execute terrorists acts that [once] would have been considered unrealistic or fantasy."
Interpol says several pathogens and viruses most likely to be used in any bio-terror attack, Mr Noble told delegates.
Tactics could vary - as well as a traditional detonation, attackers could turn themselves into a "suicide bio-weapon", Mr Noble said, travelling around while highly infectious.
Postal services could also be used to spread disease as shown by anthrax attacks in the US in 2001.
"The potential consequences of such an attack could be so far-reaching that a lack of action in preventing bio-terrorism poses an unacceptable risk to the safety of societies around the world," he said.
The Cape Town meeting follows a conference in Lyons, France, in March, in which Interpol urged governments to back a drive against bio-terror.