BERLIN, Germany (CNN) -- A doctor is being held by police in Berlin after two patients were found dead in his office and several more were hospitalized with signs of poisoning, police said.
Police received an emergency call Saturday evening after the doctor met with 12 patients, police spokesman Karsten Mueller of the Berlin police told CNN Sunday.
The dead are a 28-year-old man and a 59-year-old man, Mueller said. Their names have not been released.
One person remains in a coma in critical condition, he said. The other patients are improving and being released from the hospital.
Police do not know what the patients were given, but are expecting the results of autopsies on the two dead.
The doctor, 50, has not been named.
The doctor runs a psychotherapy clinic, which requires a medical degree in Germany.
CNN's Frederik Pleitgen in Berlin, Germany, contributed to this report.