Pope Francis has called the French priest who was killed by Islamic State militants while celebrating Mass a martyr and urged all people of faith to denounce killing in the name of God as "satanic."

Francis celebrated a morning Mass on Wednesday in memory of the Rev. Jacques Hamel. Two extremists slit Hamel's throat in his church in Saint-Etienne-du-Rouvray, outside Rouen, on July 26. Police later killed them; the Islamic State group claimed responsibility.

Several members of Hemel's dioceses and his bishop attended the Mass in Francis' hotel chapel. In his homily, Francis lamented the persecution of Christians today for their faith.

Francis called Hamel a martyr and urged all believers to "have the courage to say the truth: killing in the name of God is satanic."