An eight-year-old boy has died after a grenade exploded in an apartment in Sweden.

The blast occurred in a third floor flat in a suburb of Gothenburg in the early hours of Monday morning.

Emergency services were called to the apartment at 3.00am and found several adults and at least five children inside, one seriously injured.

The boy, who was visiting with his family at the time, died later in hospital of his injuries.

It is believed the boy was originally from Birmingham in the UK.

The Birmingham Mail reported that the newspaper had spoken to the father of the boy, who they named as Yuusuf Warsame.

He was a pupil at a school in the Sparkhill area of the city, according to the paper.

Swedish newspaper Aftonbladet said that the grenade had been thrown into the apartment's living room through an open window and the blast hit the boy, who was sleeping there.

Others sleeping in the room escaped serious injury.

The investigation has been classified as a murder/manslaughter, according to Sweden's The Local website.

Police are probing the possibility the grenade was thrown as a revenge attack.

The Local said individuals convicted of serious violent crimes were living in the residence and one of the men convicted of a fatal shooting at a restaurant last year was registered at the address.

Yuusuf grew up in Sparkhill after his parents moved there from the Netherlands in 2001, according to the Birmingham Mail.