Bucharest was shaken by a series of crimes committed in the latter half of 1970 and the first months of 1971. An unknown individual would use a hammer, a small axe, an iron bar or a knife to attack restaurant waitresses who were alone and returning from work. He struck after midnight during unusual weather conditions such as snowstorms, driving rain, high winds, freezing cold or fog. Many women would not go outside after 9:00 pm except in large groups or with men. Their terror was heightened by the police's reluctance to release details, leading to wildly exaggerated rumours. After a few crimes, the police realized that they were dealing with a serial killer; a yearlong investigation, with the help of victims who had survived, led to Rîmaru's arrest on 27 May 1971.