Boko Haram militants opened fire on northern Nigerian villages at dawn, leaving hundreds of bodies scattered everywhere, officials said.
Islamist militants sprayed bullets as they stormed driving trucks and armored vehicles last weekend, local authorities said Friday.
Reports of death tolls varied between hundreds and as many as 2,000 people.
After the militants arrived, they unloaded motorcycles and pursued residents who fled into the bush, firing indiscriminately, said Baba Abba Hassan, a local district head.
“The attack on Baga and surrounding towns looks as if it could be Boko Haram’s deadliest act,” Human Rights Watch said in a statement.
During the raid that started January 3, hundreds of gunmen seized the town of Baga and neighboring villages, as well as a multinational military base.
Attacks continued throughout last weekend, according to residents.
Though local officials gave conflicting death tolls, they agreed on the massive number of fatalities.
More than 2,000 people were killed in attacks on 16 villages, said Musa Bukar, chairman of Kukawa local government, where Baga is located. He could could not explain how he arrived at that toll.
But Hassan said hundreds of people might have been killed, but not thousands. The actual toll will be known after a head count of households is completed, he said.
At least 30,000 people were displaced, authorities said.
Days of rampage
Baga resident Yusuf Maidaji said militants looted and torched hundreds of homes after the attacks.
“The toll could be huge because the gunmen opened indiscriminate fire on fleeing residents,” Maidaji said.
Bukar said 20,000 of those displaced are camped in Maiduguri city, the capital of Borno state.
Authorities are making arrangements to bring 10,000 others from Monguno town, 60 kilometers (36 miles) from Baga. Some residents fled into neighboring Cameroon.
“If reports that the town was largely razed to the ground and that hundreds or even as many as 2,000 civilians were killed are true, this marks a disturbing and bloody escalation of Boko Haram’s ongoing onslaught against the civilian population,” Amnesty International’s Daniel Eyre said.
Boko Haram has terrorized northern Nigeria regularly since 2009, attacking police, schools, churches and civilians, and bombing government buildings. It has also kidnapped students, including more than 200 schoolgirls who were abducted in April and remain missing.
The Islamist group has said its aim is to impose a stricter form of Sharia law across Nigeria, which is split between a majority Muslim north and a mostly Christian south.
The United States condemned the attacks, saying the group “shows no regard” for human life.
“All those responsible for these recurring terrorist attacks must be held accountable,” State Department spokeswoman Jen Psaki said.