Eight people are dead and three others are seriously injured after a gun attack on a Jehovah's Witness building in the German city of Hamburg.

It is believed the massacre was carried out by a lone gunman who is among the dead; however, this has yet to be officially confirmed.

The alarm was raised just after 9pm last night were shots were fired at the hall in the Groß Borstel district of the city.

Police said the gunman opened fire after entering the building, before allegedly fleeing to the first floor.

Officers arriving on the scene then heard a shot from an upper floor and found a body upstairs.

Police spokesperson Holger Vehren said none of the officers fired their weapons.

One witness told they heard 12 continuous shots.

In a statement posted on Twitter, Hamburg Police said: “We found a lifeless person in a community centre in #GroßBorstel who we believe could be a perpetrator.

“In order to rule out the involvement of other perpetrators, we carry out checks and search extensively.”

The motive for the attack is currently unclear.

With reporting from IRN …