The men were arrested in Gujrat after police spotted posters marking the 20th anniversary of the death of priest Fazal Masih that referred to him using the Urdu word for prophet."We have arrested three men, including the son of the priest, because they used the word prophet for the late Fazal Masih," local police station chief Shahid Tanveer told AFP.He said officers had summoned local Muslim clerics and elders of the Christian community to the police station to consult them on the matter. The Christians organising the event apologised and asked forgiveness, saying they had used the word to celebrate Masih's services to religion, but the Muslim clerics refused to accept the apology, he added.Tanveer said that a case under anti-terrorism law had been registered against the organiser and three men had been arrested while 11 others were at large. He did not explain why terrorism charges were brought, though the legislation is often used in sensitive and high profile cases as it gives access to a fast-track trial process.Christians, who make up around two per cent of Pakistan's population, have been increasingly targeted in recent years, often over allegations of blasphemy. The Supreme Court agreed last month to hear an appeal by a Christian woman against her death sentence for blasphemy, lawyers said, in a case that has drawn criticism from rights campaigners.Asia Bibi, a mother of five, has been on death row since 2010 after being convicted of insulting the Prophet during a row over drinking water with Muslim women with whom she was working in a field.