The police said as per the complaint, Father Paul Pulikottil, the Vicar of the nearby Vadookara Little Flower Parish Church, had allegedly slapped the girl on July 9 in the church hall in the presence of several others.
The girl's father, Biju, who is the president of the Kerala Catholic Youth Movement of the parish unit, said the Vicar had ordered that all children who had received their first Holy Communion, should confess once every three months.
After mass on July 9, the Vicar asked the children if they had followed his orders.
When the girl stood up and admitted that she had not, the angry priest slapped her hard on the cheek, he said.
The girl's face became swollen and one of her teeth loosened up. She was admitted to a district hospital the next day and later discharged, Biju told PTI.
Police have registered a case against the priest for assaulting a minor girl under the Juvenile Justice Act 2000.
The investigation was progressing and a report would be submitted to the court shortly, police said.
Biju said pressure was being exerted on him by certain influential people to make a compromise in this regard as the priest was likely to leave for the US in two months.
He said he had met the Archbishop of Thrissur in this regard.
The Vicar was not available for his comments.
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