The attack comes exactly two weeks after a suicide bombing inside a packed Shia mosque in Pakistan's Sindh province during the Friday prayers killed 61 people, including children, in the deadliest sectarian attack to hit the country in recent times.
At least three explosions and gunfire was heard when worshippers had assembled in the Imamia Masjid Imambargah here for the 'Zuhr' afternoon Friday prayers.
So far, 20 people have been killed and over 50 others have been injured, hospital sources said.

Three suicide bombers entered the mosque while only one was able to denonate the bomb. Another suicide bomber was killed by security forces while the third one was arrested in an injured condition, quoted SSP operations Mian Saeed as saying.
The suicide jackets of the suicide bombers are being defused by bomb disposal squad, the report added.
There were also reports that some militants were still in the mosque and are still exchanging fire with security forces.
Television footage showed images of people running frantically as the area was covered with thick smoke.
The attack is a reminiscent of the December 16 Peshawar school carnage last year that killed at least 150 people, including 136 students.


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