German prosecutors said Friday they have launched an investigation against the district chief of the flood-hit region of Ahrweiler for negligence as warnings were made belatedly, resulting in the deaths of dozens of residents.

Some 189 people lost their lives in severe floods that pummelled western Germany in mid-July, raising questions about whether enough was done to warn residents.

Following an initial examination of the case, prosecutors in Koblenz said they have "affirmed the initial suspicion of negligent homicide and negligent bodily harm... and have initiated investigations."

Ahrweiler district chief Juergen Pfoehler is the focus of the probe because he had "sole decision-making authority" and was meant to be in charge of the operation according to current regulations.

Another member of the crisis group, who had for at least part of the time taken over the command of the emergency response, was also under investigation, prosecutors said, without naming the suspect.

After reconstructing the events, investigators found that forecasts about the impeding floods should have led officials to sound the warning and evacuate residents living near the swollen Ahr river by 8:30 PM (1830 GMT) on July 14.

-This, according to the initial suspicion, was obviously either not carried out, or not carried out with the required clarity or only carried out belatedly, such that it could amount negligence- said prosecutors.

Sixteen people are still missing after torrents of water ripped through towns and villages, destroying bridges, roads, railways and housing in the region's worst flooding disaster in living memory.