Munich, Germany: Nine people were killed and 16 wounded in a shooting rampage by a teenage gunman at a Munich shopping centre on Friday.

Investigators found the body of the suspected shooter, who appears to have acted alone and then killed himself.

Police say the assailant was an 18-year-old German-Iranian who was not previously known to police.

Europe has been on alert in the wake of a string of attacks in neighbouring France and in Belgium.

Here is what we know:

- What happened? -

A shooter opened fire at a McDonald's restaurant and continued onto a street before entering the Olympia mall near the Olympic stadium in Germany's third biggest city.

The shooting started shortly before 1600 GMT, with authorities initially saying witnesses reported seeing three gunmen. But police later said the assailant likely acted alone.

Nine people were killed and 16 injured including children, Munich police said.

A video posted on social media appeared to show a man dressed in black walking away from the McDonald's while firing repeatedly on people as they fled.

Another video appeared to show the gunman on the roof of a parking garage exchanging a tirade of insults with a man on a nearby balcony.

"I'm German, I was born here," the assailant is heard to reply after the man fired off a volley of swear words, including an offensive term for foreigners.

Authorities evacuated the main train station in the city of some 1.4 million people, while metro and bus transport services were suspended, but have since resumed.

Elite anti-terror police launched a massive search operation in the Bavarian capital before the authorities announced the suspect had committed suicide.

The mall is near the stadium for the 1972 Olympics and the athletes' village, which was the site of the massacre of 11 Israeli athletes by the Palestinian Black September group during the Games.

- Who was the gunman? -

Local police chief Hubertus Andrae said the shooter was an 18-year-old dual-citizen German-Iranian from Munich.

"The motive or explanation for this crime is completely unclear," he told reporters, adding that the suspect had no criminal record.

The teenager's home was being searched and his friends and family being questioned.

Andrae said the attacker had shouted out during his spree, without elaborating, while some media suggested it was a jihadist slogan.

A police spokesman had earlier said they suspected "terrorism" but that there were no immediate indications of an Islamist link.

Police said two other people who had been thought to be linked had "absolutely nothing to do" with the attack -- and that they were simply fleeing the scene.

- Wave of attacks -

The rampage happened just days after a 17-year-old asylum seeker went on a rampage with an axe and a knife on a regional train in Germany on Monday, injuring five people, two of them critically.

Interior Minister Thomas de Maiziere said the teenager was believed to be a "lone wolf" attacker who appeared to have been "inspired" by the Islamic State group but was not a member of the jihadist network.

The assailant -- believed to be an Afghan or Pakistani -- or had arrived as an unaccompanied minor in Germany in June 2015.

On July 14, Tunisian Mohamed Lahouaiej Bouhlel rammed a lorry into crowds enjoying a firework display on the seafront promenade in the French Riviera city of Nice, killing 84 people including children.

It was the third major attack on French soil in the past 18 months, after the Islamic State carnage at Paris nightspots and cafes in November and the shootings at a satirical magazine and kosher supermarket in January 2015.

The IS group also claimed suicide bomb attacks at Brussels airport and a city metro station in March that killed 32 people.

In May, a mentally unstable 27-year-old man carried out a knife attack on a regional train just southeast of Munich, killing one person and injuring three others.

Friday's carnage came on the fifth anniversary of right-wing fanatic Anders Behring Breivik's massacre in Norway that killed 77 people.

- Migrant influx -

Bavaria became the main gateway for hundreds of thousands of migrants and asylum seekers arriving in Germany, Europe's biggest economy.

Hate crimes and attacks against migrants exploded after arrivals spiked to more than one million last year, mostly from the Middle East and Africa.

Some 923 offences against refugee shelters were reported in 2015 including 177 acts of violence, a sharp rise from the previous year, according to figures from the interior ministry.

AFP