A Kazakh man has been hacked to death in broad daylight in the middle of a German street with a 'samurai sword', police said.

The dead man's Syrian roommate was arrested after the 36-year-old victim was repeatedly stabbed in Stuttgart yesterday in front of horrified onlookers.

Authorities confirmed a man was killed in the road in the German city Fasanenhof district with a 'sword-like object' that looked like a samurai weapon.

Screaming witnesses tried in vain to save the man as he was hacked at by his attacker, but he died at the scene.

The suspect then reportedly fled on a bicycle but was caught that evening following a frantic police helicopter manhunt.

Officers also found a 'sword-like object' discarded in a bush near the scene, thought to be the murder weapon.

The attacker (left and right) was seen repeatedly stabbing the victim in the middle of the road in Stuttgart as horrified onlookers (right) tried to save him

After hacking the 36-year-old man to death the suspect ran

Police and prosecutors said today that a 28-year-old Syrian man who apparently had shared an apartment until recently with the 36-year-old victim was arrested.

There was no immediate details of a possible motive for the stabbing yesterday evening, which followed an argument between the two men.

The victim - who has not been publicly identified - is believed to be of German-Kazakh origin and used to share a flat in the city with the suspect, Welt reports.

According to Bild, the suspect was heard by witnesses repeatedly shouting at the victim: 'Why did you do that?' However, the motive behind the attack has not been revealed.

Footage of the brutal slaying was shared on social media today and has been viewed more than 10,000 times.

It shows hysterical bystanders screaming at the suspect to stop as he stands over his helpless victim in the middle of the street and repeatedly slashes him with the sword.

Watching from the balcony of a nearby apartment, the woman filming says: 'Call the police. Did you call the police?'

A man replies: 'Yes, I did. He's totally stabbing him.'

The victim lying on a street in Stuttgart, Germany, yesterday. He died at the scene after being repeatedly stabbed in the middle of the road

The attacker is then seen lifting the sword above his head and plunging it repeatedly into the victim.

A second more graphic clip filmed by another resident shows the suspect threatening members of the public as they try to intervene and rescue the victim.

After ordering them to get back he lifts up the sword and brings it down on the bloodied victim once more before running away.

A spokesman for Polizei Stuttgart told Bild: 'We have arrested one person and it is being investigated whether they qualify as the perpetrator.'

Stuttgart is the capital of the southern German state of Baden-Württemberg and is the sixth-largest city in Germany. It is generally regarded as one of the country's safest cities, according to Welt, with several major car manufacturers headquartered there.

Social media viewers were left traumatised by the footage. Krisi Romi said: 'I'm still stunned, where is this supposed to end?'

Anes Merdanovic called it 'just sick'. Manuel Longwitz added: 'I can't find the words.'