ABUJA, Nigeria, May 7 (UPI) -- Boko Haram, a radical Islamist militant group, launched a 12-hour attack on the Nigerian village of Gamboru Ngala Monday afternoon, killing around 300 people.

The militants fired rocket-propelled grenades and improvised bombs into a crowded outdoor marketplace while shouting "God is great" from their armored vehicles.


Sources told CNN that the fighters set fire to the buildings where people had fled to escape the attack. According to the regional leader of the village, anyone who tried to run out of the burning buildings was shot.

The militants were met with resistance while attacking the local police station until they used explosives to blow off the roof of the building. Fourteen police officers were found dead inside.

"While calling on the general public to be part of the solution to the present security challenge, the Police High Command also reassures all citizens that any information given would be treated anonymously and with utmost confidentiality," said the Nigerian police in a statement.

The details of the attack emerged one day after the U.S. announced that they will be sending assistance to help authorities search for the 276 girls abducted by the group last month. The police have offered a $310,000 reward for information leading to the missing girls, as frustration continues to grow internationally at the lack of progress in the search.