gerardo ordaz
Police say they found Gerardo Ordaz standing naked in a police station car park carrying his daughter Healdsburg Police Department

A California man has been arrested on suspicion of drowning his four-year-old daughter in a church pool used for baptisms before walking naked to a police station with her body.

Gerardo Mendoza Ordaz, 42, of Healdsburg, was found at the local police station car park yelling for help while holding his soaking wet daughter in his arms on Sunday night (20 November), Healdsburg Police Chief Kevin Burke said.

Ordaz's partially clothed nine-year-old son was said to be standing next to him when he was found in the car park. The unresponsive girl was later taken to hospital where she was pronounced dead.

Officers believe the incident took place at Healdsburg's St John the Baptist Catholic Church, which is routinely left unlocked on a Sunday evening and has a baptismal pool at least a foot deep.

"This is very unusual. I've never seen anything like it in my career," Burke told local news station Kron 4.

"We believe the four-year-old girl drowned, the father is responsible, and it occurred inside the church in the baptismal pool.

"We cannot disclose a motive at this time, but we determined it was not accidental."

Police arrested Ordaz, who lives with the child's mother, after a statement was taken from his son, who was reportedly present inside the church at the time of the incident.

Police did not confirm if the suspect had admitted to causing the death.

Father Sean Rogers, pastor of St John's, said in a statement: "Sunday night there was tragedy in the church; a little girl lost her life. When police finish the investigation we will know more. In the meantime, please pray for the family, and the parish community."

Police also reportedly searched the family's home, adding they had no records of domestic violence calls from the address.

Ordaz is being held in Sonoma County Jail on a murder charge. He is due in court on Tuesday.

St. John the Baptist Catholic Church
Investigators believe the girl drowned in Healdsburg's St John the Baptist Catholic Church Google Streetview