Police in the city said  a 60-year-old man and a 45-year-old woman have been injured int the blast at the Varby Gard metro station in the Huddinge district.
The man is reportedly in serious condition in hospital but the condition of the second blast victim is unknown..
Officers said initial reports suggested the man was injured when he picked up an object, possibly a hand grenade, which then exploded in his hands.
They said there was no evidence to suggest the bast was terror-related.
A police spokesman said: “Police patrols have encountered a person injured in what is believed to be an explosion. 
“After talking to a person who was in the company of the injured party, it appears that the explosion was caused by an object from the ground.”
The spokesman said the bomb squad was on its way to the scene to investigate the cause of the explosion.
Stockholm fire department spokesman Lars-Ake Stevelind told Sveriges …