Unknown gunmen opened fire on the men on Thursday evening in Anyiin, in the Logo area of Benue state, where early last month more than 80 people were killed.
But given the location and similarity to previous attacks, suspicion locally immediately fell on herders.
Owoseni said officers sent to the scene at the sound of gunshots found that four people on two motorcycles had been attacked, with three others collecting water.
"Three survivors are still receiving treatment at the hospital. (They) happened to be those that were fetching water from the stream," he said.
"The ones that were dead were those riding on the motorcycles while one of them survived."
More than 168 people have been killed in communal violence between herders and farmers this year alone, with about 100 in Benue state, according to Amnesty International.
In 2016, some 2,500 were killed countrywide, the International Crisis Group has said, warning the conflict was becoming "as potentially dangerous as the Boko Haram insurgency in the northeast".
The long-running clashes began as a dispute over land and water but have escalated in recent years, stoked by ethnic, sectarian and religious differences.
The farmers are mainly Christian while the cattle herders are Muslim, accentuating deep-seated mistrust between Nigeria's south and north.
Buhari this week rejected claims a government proposal to create cattle ranches to contain herds was an attempt to "colonise" any part of Nigeria.
The army has announced it would deploy extra troops to Benue and neighbouring Taraba and Nasarawa state to try to stop the unrest.
Benue's governor, Samuel Ortom, has criticised the police for not doing enough to protect people and property and this week urged people to use "any lawful means" to defend themselves against attack.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)