A passerby alerted the police, who closed the Prager street and evacuated the apartment building in the Floridsdorf district.
Christoph Pölzl said that alongside special forces teams members of the Vienna Ambulance Service and the Fire Department were also present as a precaution.
After several hours a police negotiator was able to make contact with the young man, an Egyptian citizen, who was hiding in his apartment. He opened the door of his own accord and did not resist arrest. An explosives expert searched his apartment but did not find anything.
Police said the man was examined by a doctor and later taken to hospital. It's believed he's suffering from mental illness.