BERLIN — A male nurse who was convicted of killing patients in Germany with overdoses of heart medication is now believed to have killed at least 86 people — and the true scale of the killings could be even larger, investigators said Monday.
Many of the deaths could have been prevented if health authorities had acted more quickly on their suspicions, said Johann Kuehme, police chief in the northwestern city of Oldenburg.
Niels Hoegel, now 40, was convicted in 2015 of two murders and two attempted murders at a hospital in the northwestern town of Delmenhorst. He was sentenced to life in prison. But prosecutors have long said they believe he killed many more people, last year putting the figure at 43 at least.
The crimes came to light after Hoegel was convicted of attempted murder in another case. Authorities subsequently investigated hundreds of deaths, exhuming bodies of former patients in Delmenhorst and nearby Oldenburg.
Kuehme said Monday that authorities have now unearthed evidence of 84 killings in addition to the ones for which Hoegel was convicted. The number of actual killings is likely higher because some possible victims were cremated, making it impossible to gather evidence, Kuehme added.
‘‘Eighty-four killings . . . leave us speechless,’’ Kuehme told reporters. ‘‘And as if all that were not enough, we must realize that the real dimension of the killings by Niels H. is likely many times worse.’’