The president gave the assurance when he hosted members of the Kannywood entertainment industry to a dinner at the Presidential Villa, Abuja.
He said that the Federal Government would not allow any group hiding under religion to unleash terror on innocent citizens.
Buhari, who spoke in local language, said: “It’s totally wrong for any believer in God to kill innocent people either in the Mosque, Church or the market place.
“You can’t be shouting Allahu Akbar (Allah is Great), Allahu Akbar, and killing innocent citizens and destroying properties all in the name of God.
“It is either you don’t know what you are saying or you don’t even believe in the existence of God Almighty. God has nothing to do with injustice.
“So, now we are confronting them and by the grace of God we will destroy them.’’
Buhari, who recalled his political struggles since 2003 when he made his first attempt to clinch the presidential seat, lauded former President Goodluck Jonathan for accepting defeat in the 2015 general elections.
“I’ll continue to hold former president Jonathan in high esteem as a result of that singular act.
“He (Jonathan) was in power as Deputy Governor, Governor (Bayelsa), Vice-President and President, all for about 10 years and he voluntarily accepted defeat and surrendered power to me,’’ he said.
The president enjoined members of the Kannywood to use their respective talents in promoting the culture of peaceful co-existence and unity among the diverse socio-political groups in the country.
Earlier in his remarks, the Secretary to the Government of the Federation, Mr Boss Mustapha, expressed the hope that Buhari had been guaranteed at least five million votes in the 2019 presidential election by the fans and followers of the entertainers.
He, therefore, urged them to use their platforms in the social media in promoting the achievements of the Buhari administration.
Mustapha thanked entertainers for the roles they played in 2015 which contributed immensely to the victory of Buhari in the presidential election, and called on them to repeat the same in 2019.
Representatives of the Kannywood entertainers, who spoke at the event, pledged to mobilise support for Buhari and other APC candidates in the forthcoming 2019 general elections.