A man who went on a killing spree across German bars had posted an online rant calling for a “complete extermination” of foreigners and people of different faiths, authorities say.

Police are now considering the mass murders a case of domestic terrorism, after it was discovered the killer had been posting extremist videos containing “confused ideas and far-fetched conspiracy theories”.

The gunman was a 43-year-old local living with his parents in the town of Hanau, 25km east of Frankfurt, near the scenes of the mass shootings in which at least nine people were murdered, including his mother.

Chancellor Angela Merkel said the events exposed the “poison” of racism in Germany and she pledged to stand up against those who seek to divide the country.

People take part in a commemoration ceremony for the victims of the attack in Hanau. Photo: Getty

What we know about the killer

Authorities revealed his name to be ‘Tobias R’, releasing just his surname in line with local police’s usual practices. Local media later confirmed his full name was Tobias Rathjen.

On a since removed personal website, the man wrote that he was born in Hanau in 1977 and grew up in the city. He worked as a bank clerk and earned a university business degree in 2007.

A photograph of a younger Tobias Rathjen. Photo: Getty

Rathjen had posted a 24-page document of ramblings police said revealed he was “deeply racist”.

A member of his local sports shooting club, Rathjen was a licensed shooter and owned multiple firearms.

Research network RedaktionsNetzwerk Deutschland (RND) cited information from security circles suggesting the gun he used to carry out his attack was a Glock 17 9mm Luger which the shooter had legally bought on an online portal.

The attack must be a ‘call to action’ against hatred

It’s the fourth attack motivated by right-wing extremism in Germany in the past year.

Rathjen first attacked a shisha bar and a neighbouring cafe in Hanau about 10pm Wednesday (local time), killing several people.

He then travelled about 2.5km and opened fire again, first on a car and then a sports bar, claiming more victims.

Can-Luca Frisenna, whose family runs one of the bars, told Reuters news “everyone was shocked”.

“I heard my father was affected and my little brother… I saw them both –they were horrified and they were crying and everything,” she said.

A manhunt continued throughout the evening, with police initially fearing there could be more than one gunman.

A forensic officer at the scene outside the Midnight hookah bar, one of two bars that were targeted by the gunman. Photo: Getty

They used CCTV to track the man’s movements. They were then called to an apartment block where neighbours had spotted the getaway car.

Heavily-armed officers stormed the unit in the early hours of Thursday (local time) and found the suspect dead with gunshot wounds. The body of his 72-year-old mother was also found at the property.

Six others were injured, one seriously.

Investigators said it appeared the gunman acted alone, but German’s federal prosecutor Peter Frank said the “goal of the investigation is to find out whether there were, or are, people who knew of, or supported” the attacks.

Mr Frank said all of the victims were all people of foreign backgrounds. Turkish officials confirmed five of the dead were Turkish nationals.

Both the attacker and his mother had gunshot wounds, and the weapon was found on him, said Peter Beuth, interior minister for the state of Hesse.

Mr Beuth said it did not appear the gunman was on the radar of Germany’s domestic intelligence agency.

Turkey’s Foreign Ministry said the Hanau shootings were a call to action for the whole of Europe.

“The indifference shown in Europe to the fight against rising xenophobia has led to new attacks being added every day,” the ministry said in a statement.

“It is time to say ‘stop’ to these attacks.”

-with AAP