Three bodies were found at a rural hotel in Bavaria and two more around 400 miles away in the town of Wittingen.
The German Chancellor is under more pressure amidst populist right-wing resurgence.
Germany's leader is facing criticism over the open-door refugee policy in the wake of attacks.
Police shot the man dead after he injured four people.
Waters are expected to reach nearly six meters on Friday.
Ten people were killed and more than 80 were injured in the crash.
Copyright runs out on Hitler's autobiography in 2016 paving way for publication.
Participants in an annual neo-Nazi march in Germany unwittingly raised money for anti-Nazi activists.