At least 12 people have been killed and more than 1,000 homes burnt down in northern Nigeria.
It comes after a fight reportedly broke out earlier this week over a Christian girl converting to Islam, as we reported earlier this week.
Local media report that the violence in Kaduna state escalated in recent days, with police recovering petrol bombs and arresting 18 suspects.
While the state police chief says investigations are under way into the cause of the violence, senior politicians have been quick to suggest it was religiously motivated.
Nigeria’s Deputy Senate President Ike Ekweremadu has said: The fact that somebody is a Christian or Muslim does not mean that he should hate another person.
“We are talking about hate speech. The worst of it is hate action. We must try as hard as we can not to have any religious escalation in Nigeria.”
On Monday, an eyewitness told BBC News Pidgin that trouble started after the Christian girl from Gwari converted to Islam because of her boyfriend.
The witness said this provoked some Christian youths in the area.
Other reports suggest tensions between the two faiths had been simmering for some time.