Catholic bishop shot dead near Los Angeles church

The Los Angeles religious community is in mourning after a Catholic bishop hailed as a "peacemaker" was shot and killed just blocks from a church in Southern California.

Detectives are investigating the death of Bishop David O'Connell as a homicide, according to the Los Angeles County Sheriff's Department.

Authorities have not said whether the bishop was targeted in the shooting or if his religion was a factor in the killing.

The sheriff's department would not say how or specifically where his body was discovered on Saturday.

The shooter - or shooters - remain at large.

Bishop O'Connell, 69, had been a priest for 45 years and was a native of Ireland, according to Angelus News, the archdiocese's news outlet.

Pope Francis had named him one of several auxiliary bishops of the Archdiocese of Los Angeles - the largest in the country - in 2015.

The bishop worked in South Los Angeles for years and focused on gang intervention, Angelus News reported.

He later sought to broker peace between residents and law enforcement following the violent 1992 uprising after a jury acquitted four white LA police officers in the beating of Rodney King, a Black man.

Almost two decades later, Bishop O'Connell brought the San Gabriel Valley community together to rebuild a mission after an arson attack.

In recent years, he spearheaded Catholic efforts in the region to work with immigrant children and families from Central America.

Bishop O'Connell was found in Hacienda Heights about 1pm on Saturday with a gunshot wound.

Sheriff's deputies were called to the area - just blocks from the St. John Vianney Catholic Church, part of the bishop's archdiocese - on a report of a medical emergency.

Paramedics pronounced him dead at the scene, the sheriff's department said.

The archdiocese said Bishop O'Connell lived in Hacienda Heights - an unincorporated community about 30 kilometres east of downtown Los Angeles - but it was not immediately clear whether he was found at his home or elsewhere.

Masses at churches across the region were dedicated to Bishop O'Connell on Sunday.

The Diocese of Cork and Ross in Ireland, where O'Connell was born, was shocked by the priest's death.

Bishop Fintan Gavin said in a statement Bishop O'Connell "has always maintained his connection with family and friends in Cork" through frequent visits back to Ireland.

The LA County sheriff offered the agency's condolences, saying detectives are "committed to arresting those responsible for this horrible crime".

"He was a peacemaker and had a passion (for) serving those in need while improving our community," Sheriff Robert Luna said on Twitter.

The violence was the latest to rock religious leaders in Los Angeles.

Two Jewish men were shot and wounded last week by a gunman who authorities said targeted them for their faith.

Suspect Jaime Tran has been charged with federal hate crimes.