A man has died after he picked up a hand grenade outside a metro station in Stockholm.

The incident took place outside Varby Gard underground station in Huddinge, a southern district of the Swedish capital.

Witnesses say the device exploded as soon as the 60-year-old grabbed hold of it.

Paramedics took him to hospital, but he did not recover, and died earlier this afternoon.

A woman, 45, suffered serious facial injuries in the explosion and is currently receiving treatment.

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A man, 60, and woman, 45, have been taken to hospital following an explosion outside Varby Gard underground station in Huddinge, greater Stockholm

Police stand on guard at the scene outside Varby Gard metro station this morning

An ambulance races away from the scene in Huddinge, greater Stockholm

Local media in Sweden have reported that the blast was from a hand grenade although this has not been confirmed by police, who claim it is too early to comment.

Officials say the blast is not believed to be terror-related.

Police do not believe the incident was a planned attack on the two people injured.

A police spokesman said: 'It is too early to say. Technicians are still working on it. Nothing indicates that the (injured) couple were targeted.'

Rescue official Lars-Ake Stevelind told Swedish broadcaster SVT that 'someone has used some type of explosive material' for the object and that police were investigating it.

The underground station and a nearby square have been shut since the incident as police and bomb squads comb the scene for evidence.

Armed police have arrived at the scene and the area has been cordoned off to look for evidence