Protesters flooded Makurdi, the capital of Nigeria’s eastern Benue state, following attacks on Monday and Tuesday that reportedly saw Fulani herdsmen kill 20 farmers in Guma and Logo local government areas.
The mainly Muslim nomadic cattle rearers have been clashing with largely Christian farmers over grazing rights in Nigeria for decades.
“This is one attack too many, and everything must be done to provide security for the people in our rural communities,” Buhari said in a statement.
At a press conference on Tuesday, Benue governor Samuel Ortom said that more than 20 people were killed in the violence, though an official toll has yet to be released.
“People were slaughtered like animals,” Ortom was quoted as saying by Nigerian newspaper The Guardian.
More than 1,000 people took to the streets of Makurdi and blocked the highway on Wednesday morning, according to Helen Teghtegh, the head of local non-governmental organisation Community Links.
“There have been no policies implemented to slow down the attacks made by Fulani herdsmen,” she said.
“We feel that (President Buhari) being a Fulani man, he’s turning a blind eye on the issue.”
Teghtegh said another protest was planned for Thursday.
The killings usually occur at the end of rainy season between December and March, when the Fulani pastoralists arrive in large numbers to graze their cattle and the farmers start harvesting yams.
But as the country’s population explodes — Nigeria is set to become the world’s third most populous country by 2050 according to the UN — the battle over land is intensifying.
Hundreds of people were reported dead in Benue state in early 2016 following a week-long clash between herdsmen and farmers.
In November, at least 30 people were killed after farmers attacked herdsmen in the Numan district in eastern Adamawa state.
The violence is a perennial security headache for Nigeria, which has been battling Boko Haram Islamists in the northeast since 2009 and a flare-up of militancy in the oil-producing south.
The International Crisis Group, a Brussels-based think-tank, said in a September that some 2,500 people had been killed and tens of thousands were forced from their homes last year.
Such attacks were “becoming as potentially dangerous as the Boko Haram insurgency in the northeast”, it added.