Mr Buhari stated this in Abuja when he played host to Eminent and Respected Citizens of Niger State.
The delegation led by Governor Abubakar Bello, visited the State House, on Tuesday.
“I was taken aback by what is happening in the North West and other parts of the country,” presidential spokesman, Femi Adesina, in a statement, quoted his principal as saying.
“During our campaigns, we knew about the Boko Haram. What is coming now is surprising. It is not ethnicity or religion, rather it is one evil plan against the country,” the president added.
The Nigerian leader promised to increase the war tempo against the terrorists and bandits.
“We have to be harder on them. One of the responsibilities of government is to provide security. If we don’t secure the country, we will not be able to manage the economy properly,” the statement partly read.
His visitors said they visited to show appreciation to the president for his interventions on infrastructure, security, and appointment of indigenes of the state into key positions of government.
Boko Haram, a terrorist organization based in northeastern Nigeria has killed many and displaced thousands of Nigerians since it was formed in 2002.
When he sought to be president in 2015, Mr Buhari vowed to wipe out the terrorists by leading from the front. Despite efforts being made by his administration which claimed to have decimated the terror group, the terrorists are still carrying out pockets of attacks here and there.