ZABARMARI, NIGERIA – For years, the farmers had an agreement with Boko Haram militants: They could tend their fields in peace, as long as they did not report the fighters' presence to the Nigerian Army.

But just over a week ago, that deal was broken. The Islamic group killed more than 70 farmers from Zabarmari, a village in northeastern Nigeria, residents say. The militants accused the farmers of betraying them.

"Everything is shattered now," said Ibrahim Abubakar, 36. Four of his friends were beheaded, he said.

People in rural areas of northeast Nigeria, Africa's most populous country, have largely been left at the mercy of Boko Haram by a government whose security forces have mainly retreated from the countryside to protected garrison towns.

Villagers are caught in a deadly Catch-22. If they report the militants to Nigerian authorities, they risk gruesome reprisals by Boko Haram, a group known for abducting schoolgirls and killing tens of thousands of people. If they stay silent, they risk the wrath of the Nigerian military, which has been accused of routinely shooting villagers dead and burning their houses down.

In Zabarmari, villagers struggle to eke out a living through subsistence farming and fishing.

"We are accused of being collaborators by both the security operatives and the insurgents, when all we did was" look for peace, said Garbati Sani, a village elder. "What do we do to stay safe?"

Surviving farmers said that they would return to their fields because there was no way they could eat otherwise. Conflict and other conditions in northeastern Nigeria have made the people there desperately hungry, and the region could face a famine in the next few months if nothing is done, according to the United Nations World Food Program.

Villagers in Zabarmari said that those killed were mostly young men, many of them the breadwinners in their families.

On the morning he was killed, one of the farmers, Zakariyau Mohammed, 20, told his father to rest up while he went to the farm.

"I didn't know it was the last smile I would ever see on his face," said his father.