The doctor's practice is in the vicinity of the town's central train station, which police evacuated in the early afternoon due to a “threatening situation.”
The emergency call came in after several witnesses heard gunshots at around 12.50pm in the building in which the practice is based.
At the scene investigators found that both of the corpses had several bullet wounds in them. But who shot at them and why they were killed still remains unclear.
It is also unknown whether the killer is still on the loose or whether one of the doctors killed the other before taking his own life.
Prosecutors would not comment on whether one doctor killed the other but said: “As far as we know, no other person was caught up in the incident.”
Bild reports prosecutors saying that “there is no longer a threat. Residents need not fear.”
Both of the deceased are said to be middle-aged males. At this stage no more is known about their identities.
The information on the deaths comes from prosecutors in the university town of 70,000 inhabitants.
Violent incidents are not uncommon in doctors' practices, with patients usually attacking doctors when such incidents do occur.
In late July a senior doctor at a Berlin hospital was killed after one of his patients shot him.
In 2012 a pensioner in Rhineland-Palatinate shot and killed two doctors before taking his own life. The exact background to the attack was never fully explained, but prosecutors said the man suffered from a personality disorder.