A statement issued by the police spokesman, Jimoh Moshood said Buhari gave the order on Monday night, January 8, 2018.
The spate of killings which began in the wake of the new year has claimed a total 71 lives, according to the State government.
The IGP is said to be making plans to move to Benue with additional five units of Police Mobile Force (PMF).
On Sunday, January 7, the police boss deployed, among other security measures, five MOPOL units.
More Units of the Police Special Forces, Counter Terrorism Units, and Conventional Policemen were also deployed to the State on Monday.
"The Aerial Surveillance by Police Helicopters will continue, while the Police Mobile Force Personnel, Police Special Forces and conventional Police Personnel, the Counter Terrorism Unit (CTU), Police Explosive Ordinance Department (EOD) and Special Police Joint Intelligence and Investigation Teams already deployed to Benue State will carry on relentlessly with the patrols and crime prevention activities in the affected areas to sustain the normalcy that have been restored in the State", the statement said.
"The Force will not hesitate to deal decisively with trouble maker(s), any group(s) or individual for conduct likely to instigate the escalation of the crisis. The full weight of the law will be applied on anyone arrested for being responsible for the mayhem in the affected areas in the State.
"While once again, the Nigeria Police Force commiserate with Government and the people of Benue State over the loss of innocent lives, the Force implored them to cooperate with the Nigeria Police Force in this latest effort to restore lasting peace in the State.
"The commitment of the Nigeria Police Force to ensure Law and order and protection of lives and property of all Nigerians throughout the Country remains unequivocal and unwavering."
As part of the measures to stop the bloodbath in Benue, a strategic meeting, which was attended by the IGP, Governors and the Minister of Interior, Lt. General Abdulrahman Dambazau, was held in Abuja.
Governors of Benue, Taraba, Plateau and Nasarawa, Adamawa, Niger and Kaduna States were present at the meeting.
Speaking after the meeting, Governor Samuel Ortom of Benue said there is now synergy among the security agencies, the Federal and State governments to combat the challenge.