Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Bioterrorism is terrorism involving the intentional release or dissemination of biological agents. These agents are bacteria, viruses, or toxins, and may be in a naturally occurring or a human-modified form. As biological agents usually are extremely difficult to detect and do not cause illness for several hours to several days, terrorist attacks involving biological weapons are very dangerous. Learn more about the biological weapons and what can happen if they fall into the wrong hands in this book.