On Sunday, Nigeria-based militant Islamist group Boko Haram raided Kamuyya village in northeast Nigeria, killing 20 people.

Locals told Nigeria’s Daily Post that Boko Haram members had previously come to the town two months ago. They requested the citizens pay a tax of 250,000 Nigerian Naira ($1500 US) currency so “God’s work” can be carried out. When the Islamists returned, they were apparently infuriated that the locals, many of whom lived in abject poverty, could only raise 70,000 Naira.

A local told the Daily Post, “Actually, when they issued such threat, we all took it lightly, as we are all relaxed, and nobody bothered to make any extra effort to put in the amount they requested. Maybe that was what ignited this bloody attack because we were unable to meet their demand.”

Boko Haram members believe in a society that strictly follows the Shariah, or Islamic law. Under Shariah law, non-Muslims must pay a Jizya tax because, since they are not Muslims, they are viewed as second-class subjects.

The raid comes just days after a Boko Haram attack on Kimba village, where the radical Islamists burned down the entire town.

Boko Haram’s aggressiveness has increased exponentially. Just last week, Boko Haram militants killed over 100 people after multiple raids.

The insurgents were heavily armed with automatic rifles and explosive devices. They struck a popular marketplace in Kamuyya village, killing 20 and likely wounding dozens of others. The Boko Haram militants also burned down vehicles and shops within the marketplace.

The terrorists were in and out of the area before any Nigerian security personnel could arrive to help. “Throughout the onslaught which lasted for over five hours, there was no single security personnel to confront the invaders as they had a field day wreaking havoc on us,” said a local resident.

Kamuyya is located in Biu Local Government Area of Borno State in northeast Nigeria. The village is within close proximity to the Sambisa Forest, a Boko Haram stronghold. It is also near Chibok, where almost 300 Nigerian schoolgirls were kidnapped by the insurgent group last month.