BERLIN (AP) — German prosecutors say they expect to bring new charges against a male nurse already serving a life sentence for two murders after determining that he might have killed another 84 patients, if not more.

Oldenburg state prosecutor Martin Koziolek said Tuesday he expected his office would be bringing more charges by early 2018 against inmate Niels Hoegel. Additional convictions could affect Hoegel's possibility of parole, but there are no consecutive sentences in Germany.

Hoegel, now 40, was convicted in 2015 of two murders at a hospital in the northwestern town of Delmenhorst.

As part of a wider investigation that included a second hospital in Oldenburg, authorities said Monday they'd unearthed evidence of 84 additional suspected murders, and were awaiting toxicology results on 41 other fatalities.