Several killed in knife attack in Germany's Wuerzburg

 Several people were killed and others injured on Friday in the southern German city of Wuerzburg, police said, with media reporting a knife attack.

"The attacker was overpowered after the police used firearms. There are several injured as well as fatalities," said police on Twitter, without giving details on the suspect's motives.

German news outlets reported that the suspect had attacked people in the city-centre with a knife.

Police were able to arrest the man after shooting him in the leg, the Bild newspaper reported, adding that at least three people were killed and six others injured.

While the motive and full identity of the perpetrator have not yet been established, Germany has been on high alert after several deadly Islamist extremist attacks.

Suspected Islamists have committed several attacks in Germany in recent years, the deadliest being a truck rampage at a Berlin Christmas market in December 2016 that killed 12 people.

The Tunisian attacker, a failed asylum seeker, was a supporter of the Islamic State jihadist group.