Aug 02, 2017, 0:28
The incident took place around 8:30 pm local time near Jawadia mosque in the city but the type of the explosion has not been ascertained so far.
The death toll is expected to rise, according to local officals.
There is no immediate claim of responsibility for the attack.
A suspected suicide bomber first blew himself up among worshipers, and later a second assailant inside the mosque started shooting at people indiscriminately, Ayub said.
The Herat attack was the latest in a series of assaults on Afghanistan's minority Shiite population.
Other images circulating on social media show bodies lying on the floor outside the mosque.
Afghanistan is still suffering from insecurity and violence years after the United States and its allies invaded the country in 2001 as part of Washington's so-called war on terror.
It is believed the attack was a suicide bombing.
A security source, who declined to be named, said IS could prove to be more risky than the Taliban in Afghanistan.
On June 15, a terrorist attack on a Shia community mosque in capital Kabul involving at least two suicide bombers killed at least six people.
It also called "on the Muslim people of Afghanistan, as well as on the religious scholars, to stand united against the barbaric actions of the terrorists".
This is published unedited from the PTI feed.
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