Nine people were killed in a terrorist attack at a mosque in northeastern Burkina Faso, local sources said Thursday.

The attack broke out during nightfall on Wednesday in the village of Goulgountou in Burkina's Sahel region, when terrorists arrived on motorbikes and herded worshippers inside the mosque, a witness said. 

"They separated out the women, children and elderly and then made sermons to try to convince worshippers of abandoning" their form of faith, the source said.

The source explains that the terrorists brought up a discussion with the Imam, and because he refused, he was executed.

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"They tried to cut his throat, but he fought back, saying he wanted to die standing up, so the terrorists shot him in the head," a local resident said, adding that he had attended the victims' funeral on Thursday.

The source added that eight other worshippers, mainly community leaders, were shot dead in the same way. 

Thousands of people have died and more than two million people have fled their homes since terrorists began launching attacks on Burkina Faso from neighboring Mali in 2015.

More than a third of the country's territory lies outside of government control.

The insurgency fueled two coups last year among army officers angered at the rising toll.

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