Inspector General of Balochistan Police Mohsin Hassan Butt said the imam of the mosque was killed in the explosion.
“The blast was carried out through a timed device that was planted under the wooden chair of the prayer leader,” said Quetta police chief Abdul Razzaq Cheema.
No group has claimed responsibility for the blast.
The security forces cordoned off the area to collect evidences and conduct investigations.
This is the fourth explosion that has taken place in Quetta over the past four weeks. On July 23, a blast had occurred in the Eastern Bypass area which left four people dead and 32 injured.
On July 30, another attack took place near a police station in which five people were killed and 30 others were injured. The banned Tehreek-i-Taliban Pakistan had claimed responsibility for that blast.
Last week, a man belonging to the Shia Hazara community was killed and 13 others wounded in a bomb explosion in a shoe market near Quetta's busy Meezan Chowk.
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