High-security laboratories that handle the most dangerous viruses and bacteria have reported more than 100 accidents or near-misses to safety regulators in the past five years, UK official reports reveal, according to Guardian.

One blunder led to live anthrax being sent from a government facility to unsuspecting labs across the UK, a mistake that exposed other scientists to the disease. Another caused the failure of an air handling system that helped contain foot and mouth disease at a large animal lab.

Wear and tear also caused problems and potentially put researchers in danger. At a top security Ministry of Defence lab, tears were found in isolation suits at a facility handling animals infected with the Ebola virus.

Reports obtained by the Guardian from the Health and Safety Executive (HSE) reveal that more than 70 incidents at government, university and hospital labs were serious enough to investigate. Many led to enforcement letters, or crown prohibition notices, ordering labs to shut until improvements were made. Some were so serious they ended in legal action.