The incident happened around 6:30 am in the Trenz area when people were coming out of the mosque after morning prayers.
"People found a glass-like object near a shoe rack outside the main prayer hall of the mosque. When one of them tried to remove it, the grenade kept under it exploded," a police official told NDTV.
Sources say that another grenade was found by the police outside the mosque.
The injured have been shifted to the hospital.
On Wednesday, four people were injured when terrorists hurled a grenade at a patrol party of security forces in Khanyar area in Shopian.
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