A community tipster alerted police after Medina returned to his own home on Saturday while acting "irrationally" and speaking of debts the bishop owed him. Police say it is unclear whether the shooting arose from a specific dispute, however.
"I am not certain of any dispute," Luna said. "That’s something that came up from one of the witnesses, but as all of you know, our investigation continues, which means interviewing multiple witnesses to find out and get a better picture of what happened here."
CA CONVICTED KILLER DIAGNOSED WITH TERMINAL CANCER TO BE RELEASED
Investigators say Medina's wife is cooperating with the investigation, according to the New York Post.
Deputies responded to the shooting at Hacienda Heights on Saturday after a church deacon went to check on the bishop. When police arrived at the scene, they discovered O'Connell with a gunshot wound to the chest, and he was pronounced dead.
O'Connell, 69, was named an auxiliary bishop of the Archdiocese of Los Angeles by Pope Francis in 2015.
Archbishop José H. Gomez announced the news during Mass on Saturday.
"Our beloved Auxiliary Bishop David O'Connell has passed away unexpectedly," he said. "It's a shock and I have no words to express my sadness. As a priest and later a bishop here in Los Angeles for 45 years, Bishop Dave was a man of deep prayer who had a great love for Our Blessed Mother. He was a peacemaker with a heart for the poor and the immigrant, and he had a passion for building a community where the sanctity and dignity of every human life was honored and protected."
"He was also a good friend and I will miss him greatly. I know we all will," Gomez continued. "Please join me in praying for Bishop Dave and for his family in Ireland. May Our Lady of Guadalupe wrap him in the mantle of her love, and may the angels lead him into paradise, and may he rest in peace."