Story highlights Lawmaker: Boko Haram militants kill over 20 after barricading road, burning village

Residents say the group is also behind two other deadly attacks in the region

Islamist terrorist group Boko Haram has wreaked havoc in the region years

Kano, Nigeria (CNN) Militants believed to be with Boko Haram killed at least 33 people in three separate attacks in northeastern Nigeria, a lawmaker, residents and civilian vigilantes who oppose the Islamist terror group said Wednesday.

All the attacks took place in Borno state, which has been among the areas most targeted in recent years by Boko Haram.

The deadliest happened around 5 p.m. (noon ET) Tuesday, when gunmen barricaded a highway linking Maiduguri, the Borno state capital, and Damaturu, the capital of neighboring Yobe state, and killed more than 20 motorists, federal lawmaker Mohammed Sanda said.

These attackers -- who Sanda said were Boko Haram militants -- then stormed the village of Ngamdu, setting homes on fire and spurring residents to flee, said the lawmaker said.

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Boko Haram gunmen also ambushed and killed eight people traveling on a lorry, or large truck, from Maiduguri to the town of Baga, which is on the shore of Lake Chad, local vigilantes said.

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