The shootings late Wednesday targeted two shisha bars in Hanau, about 20 kilometers (12 miles) from Frankfurt, according to local media, where police launched a huge manhunt for the gunmen, presstv.com reported.
The first attack occurred at the "Midnight" bar in the center of the city around 10 pm (2100 GMT), police and reports said. Witnesses reported hearing a dozen shots, local media said.
The attacker, or attackers, then fled the scene by car, according to police. There was then a second shooting at the Arena bar.
According to local media reports, three people were killed in front of the first bar and five in front of the second.
At least five people were also seriously wounded, reports said.
An AFP journalist at the scene saw around 30 police cars leaving Hanau police station and, according to witnesses, police officers with machine guns were deployed in the city.
"The police can now confirm that eight people were fatally wounded. The search for suspects is going at top speed. There is no clear information yet as to a motive," authorities said.
Germany has been targeted in recent years by several extremist attacks, one of which killed 12 people in the heart of Berlin in December 2016.
But far-right attacks have become a particular concern for German authorities. The increase in hate crimes in recent months has prompted the country to expand a crackdown on right-wing political violence in order to repress the disturbance.
Last June, conservative politician Walter Luebcke, an advocate of a liberal refugee policy, was shot at his home.
On Friday, police arrested 12 members of a German extreme right group believed to have been plotting "shocking" large-scale attacks on mosques similar to the ones carried out in New Zealand last year.
The detainees were arrested during raids by security forces on 13 locations in six German states.
According to officials, investigations into the arrests have indicated that the group was planning to conduct simultaneous mass-casualty attacks on Muslims during prayers just like those in New Zealand.
Last week, the German Interior Ministry under the scope of the new ‘Attack Catalogue’ said there had been 184 anti-Muslim attacks in 2019, including hate speech, threats, assault, vandalism and property damage.