The gunman who killed nine people and injured 26 in a shooting spree at a shopping centre in Munich was obsessed with mass shootings, according to investigators.

Police identified the shooter as David S, an 18-year-old German-Iranian who had no criminal record. Local media named him as Ali David Sonboly.

Munich police chief Hubertus Andrae said "no evidence" of links Isis has been found in his home.

Armed police conduct searches in central Munich last night (Getty)

Mr Andrae told a news conference the attack appeared to be a "classic shooting rampage" and not an act of terrorism.

He said police were working on the assumption the attacker wanted to mark the fifth anniversary of another mass shooting in Norway, when right-wing extremist Anders Breivik killed 77 people.

Germany's top security official Interior Minister Thomas de Maiziere said other information showed the shooter had researched a 2009 school shooting in Germany, and the bomb and gun attacks in Norway by Breivik.

“There was material found in the apartment of the suspect that showed a particular interest in shooting sprees, (but) there is so far no indication of any connection to international terrorism,” Mr de Maiziere said.

The crime and perpetrator had "absolutely no" link to the issue of refugees, Mr Andrae added.

Police said the shooter, a student who was born and raised in Munich, had been in psychiatric care and treated for depression.

Prosecutor Steinkraus Koch told the news conference the suspect had a book titled: "Why Kids Kill: Inside the Minds of School Shooters."

Shoppers are evacuated from the mall yesterday where the attack happened (AFP)

Police investigator Robert Hemberger said the shooter was armed with 9mm Glock pistol and had 300 rounds.

Mr Heimberger also said it appears the shooter hacked a Facebook account and sent a message urging people to come to the mall for a free giveaway.

The posting, sent from a young woman's account, urged people to come to the mall at 4pm, saying: "I'll give you something if you want, but not too expensive."

Mr Heimberger said: "It appears it was prepared by the suspect and then sent out."

Shortly after the woman reported that her account had been hacked.

While parts of the crime scene now cleared, police said it was too soon to say when the Olympic shopping centre would re-open.

Mourners lay flowers near the OEZ mall where a shooting took place leaving nine people dead (AP)

A neighbour on Dachauer Strasse, searched by police on Saturday morning, described the alleged gunman as "very quiet".

Wishing to only give his first name, Stephan, an owner of a coffee shop, told the Press Association: "He only ever said 'hi'. His whole body language was of somebody who was very shy."

He added: "He never came into the cafe - he was just a neighbour and took out the trash but never talked."

Chancellor Angela Merkel paid tribute to the families of those killed in the attack and said: “We share in your grief - we think of you and are suffering with you.”

She added: "We will not rest until we get to the bottom of what happened."

Ms Merkel also praised the emergency services, who she said "will do everything possible to protect the security and freedom of everyone".