Three men were injured, some critically, in an attack with a Japanese long sword in a bistro in Neu-Ulm.
A 55-year-old and an 81-year-old had to be operated on immediately, the Swabia South/West police headquarters said.
However, the 55-year-old is still in a critical condition.
Another guest, aged 56, who overpowered the attacker, escaped with a minor cut.
The suspected attacker first drank alcohol in the bistro late on Wednesday evening before, about an hour later, he fetched a so-called katana sword from his nearby apartment.
According to police, on the way back to the bistro, the 28-year-old threatened a passer-by who fled and alerted the emergency services.
Arriving back at the bistro around 11:20 p.m., the perpetrator "indiscriminately and for no apparent reason attacked two guests before he was overpowered by another guest and brought to the ground," as the police described what happened next.
The suspect was brought before the magistrate on Thursday and was then taken to a district hospital.
According to the current status of the investigation, the officials assume that the man was in an exceptional psychological state.
svs/dpa