Up to 90 members of the professional fire department, volunteer fire department and rescue service as well as employees of the municipal public order service were deployed to a military base in Johanna-Kinkel-Straße. They had been alerted due to a suspicious liquid in a letter that had been opened by a post office employee.
Special units from the Cologne and Essen fire departments were called in to analyze and secure the discovery, which is being investigated further in laboratories.