A stranger attacked and injured two passers-by in Erfurt on Monday morning.
The man then fled, as the police in the Thuringian capital announced.
Among other things, a police helicopter is being used to find him.
The two attacked, aged 45 and 68, were taken to nearby hospitals for treatment.
The police initially did not disclose anything about the type and severity of the injuries.
The background to the attack was also still unclear.
The alleged perpetrator is said to be between 20 and 30 years old. He wore a brown sweater and dark sweatpants, had blonde to reddish curly hair and a scarred face. The police are now hoping for evidence of witnesses in the search.