The death of Catholic Auxiliary Bishop David O’Connell, found with a fatal gunshot wound Saturday at his home in Hacienda Heights, is being investigated as a homicide, the Los Angeles County Sheriff’s Department announced Sunday.

Paramedics who found O’Connell with a wound to the upper body in the home in the 1500 block of Janlu Avenue early Saturday afternoon pronounced him dead at the scene.

“This incident is being handled as a murder investigation. There is no additional information available,” the Sheriff’s Department said Sunday in a brief statement.

“The @LASDHQ is committed to arresting those responsible for this horrible crime,” L.A. County Sheriff Robert Luna tweeted.

Shocked parishioners and clergy in Southern California and elsewhere struggled with trying to understand how O’Connell, who they described as a peacemaker, could have met with such a violent death.

They knew him as approachable and funny, and devoted to caring for low-income and immigrant communities. The 10 a.m. Mass at our Lady of the Angels Cathedral in downtown L.A was dedicated to him, with Archbishop José H. Gomez serving as celebrant.

“Early this morning, Los Angles County Sheriff’s Department informed us that they have determined that his death was a homicide,” Gomez told parishioners. “So obviously we are deeply disturbed and saddened by this news.

“We continue to pray for Bishop Dave and his family in Ireland,” Gomez said. “We pray for law enforcement officials as they continue the investigation into this terrible crime.”

O’Connell 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,” the archbishop said in a statement on Saturday.

Just a week before O’Connell’s death, Gomez said Sunday, “Bishop Dave and I were celebrating the Mass for the Sick here at the cathedral. And he was the one giving the homily.”

O’Connell had prayed before a statue of Mary, Gomez said, and then turned to the crowd to say, ” ‘She told me to tell you that she loves you.’

“That is how Bishop Dave was … he had a beautiful devotion to our Blessed Mother. May he rest in peace,” Gomez said.

Nationally recognized among Catholic leaders, O’Connell had a prominent role in administering the church’s message and managing resources in the San Gabriel Valley region of the Los Angeles Diocese, reporting to the archbishop. O’Connell was named an auxiliary bishop for the Archdiocese of Los Angeles by Pope Francis in 2015.

O’Connell was born in County Cork, Ireland, in 1953. The Catholic Bishop of Cork and Ross, Fintan Gavin, called for prayers on his website Sunday, saying, “The news of the tragic death of Bishop David O’Connell in Los Angeles has sent shock waves across his native Diocese of Cork and Ross.”

Dan White, an acolyte with the O’Connell’s congregation at St. John Vianney Church in Hacienda Heights, said the bishop was a hard worker with an Irish sense of humor.

“He was an excellent teller of jokes,” White said Sunday morning. “A very good sense of humor, so when he was here for Mass, we knew there’d be at least four or five minutes added to the Mass because he would tell jokes before and after.”

After 15 years of camaraderie, he said, the church will suffer O’Connell’s loss for a long time.

“He has gifts that nobody else is going to step in and easily fill in,” White said. “Between the work that he did, and I mean, he has a personality. Nobody’s gonna come in and fill those shoes exactly the way he did.”

O’Connell landed in Gabriella Gil’s life when she least expected but most needed. While pregnant with her seventh child, Gil asked the bishop to bless her pregnant belly. From there, she joined him at Unbound Ministry to bring herself closer to her faith.

“I felt so understood for the first time ever by another human being who totally understands me,” she said, holding the hand of her young daughter Abigail while paying her respects at a memorial near the bishop’s home. “He always had a smile on his face. He was approachable. You could just go talk with him.”

When she heard the news of his passing, Gil spent the night awake, restless with sadness. Ultimately, Gil hopes to model his kindness to keep his memory alive.

At the cathedral Mass, parishioner Cecilia Artiga said she was stunned by the news.

“He was such a great priest and bishop,” she said in Spanish. “So many years of service and I was in shock, that a person was killed so unjustly.”

Artiga has served at the Cathedral for about four years and was inspired by his homilies.

“It felt like he was speaking with you individually,” she said.

According to the Catholic News Agency, O’Connell served as an intermediary in the aftermath of the 1992 riots triggered by the acquittal of the police officers who beat Rodney King. O’Connell tried to help build communication between police and Los Angeles’ communities of color.

When the riots drew national attention, O’Connell was in his first term at St. Frances X. Cabrini. O’Connell had traveled to Washington, D.C., to serve on a panel focused on violence in urban America and returned home to find the community in turmoil, including his parish.

“O’Connell reached out to local Catholic, Baptist, and Muslim leaders, to start a conversation and to pray together while waiting for the nightly riots to calm down,” the Catholic News Agency wrote. “He also helped in local clean-up efforts. He said that work was mostly cosmetic, but he viewed it as a symbolic gesture ‘to show that we were going to come out of it.’ ’’

More recently, O’Connell was chairman of the Subcommittee on the Catholic Campaign for Human Development of the U.S. Conference of Catholic Bishops.

O’Connell was widely described as someone who wanted to help undocumented immigrants to the U.S. get the support and legal help they needed.

He urged Linda Dakin-Grimm, a longtime commercial litigator who became close friends with the bishop, to get involved in the legal fight for young migrants caught up in the U.S. immigration system.

For about a decade, Dakin-Grimm said she’s worked pro bono for undocumented immigrants, including both unaccompanied minors and others separated from their families during the Trump administration. She said O’Connell was a constant source of support for those immigrants.

Dakin-Grimm described the ways O’Connell would make sure the children had schools they could go to once they arrived in Los Angeles.

“He would just call around to different principals of Catholic schools, telling them, ‘Hey, I need you to take this kid,’ ” she said. “Now they have the futures they do because of what he did. He did all of that totally behind the scenes.”

O’Connell also was involved in several social groups for Irish Americans — some rowdier than others. He was a fixture in the Friendly Sons of St. Patrick in Los Angeles, a local chapter of the national organization dedicated to celebrating Irish cultural heritage and charity work.

He also founded a splinter group, the Unfriendly Sons of St. Patrick, which put on an annual fundraiser for St. Michael’s Catholic School in Westmont.

O’Connell, the former pastor of St. Michael’s, was one of “the ringleaders of these well-intentioned rogues dubbed the Unfriendly Sons of St. Patrick,” administrators at Don Bosco Technical Institute, a Catholic school in Rosemead, wrote about the group in 2020. “Although they are called the Unfriendly Sons, they are in fact quite friendly.”

Dakin-Grimm said she heard the news of O’Connell’s death on Saturday. At the time, the community had heard O’Connell had died in his sleep.

“So last night when we started to see the news, we were in shock. I thought, ‘That doesn’t make any sense at all.’ I’ve said this to others already: If I had to pick somebody who would have inspired that kind of hatred —” Dakin-Grimm paused. “Bishop Dave would be way low on the list.”

The Rev. John Woolway, associate pastor at St. Pancratius Church in Lakewood, shared stories of O’Connell during Sunday’s 11 am. Mass. At St. Raymond’s Church in Downey, O’Connell arrived at the church while Woolway served an internship there while he was a young priest-to-be.

“He was there in his black cassock. I could tell this guy was cool,” Woolway said. “This is going to be a good year. And it was. He knew how to make the priesthood fun.”

Woolway recalled O’Connell’s whimsical sense of humor but added that he also had a deep affinity for the poor.

“He would organize caravans of cars to drive down to Tijuana, just south of the border, and we would bring clothing, food and supplies and take them to orphanages around Tijuana,” Woolway said. “And it’s all because Father Dave organized it. That was his passion.”

During the 10 a.m. Mass at St. John Vianney Church, the Rev. Joe Choi recalled that before his class was ordained in the ministry, O’Connell invited all nine members along with their families to join him for a dinner.

“He wanted to know who we were and where we came from,” Choi said. “That’s Bishop Dave. It wasn’t just about getting to know you, he wanted to know everything about you so he could share the gift of God’s love.”

O’Connell studied for the priesthood at All Hallows College in Dublin and was ordained to serve in the Archdiocese of Los Angeles in 1979. After ordination, he served as associate pastor in several parishes and as pastor at St. Frances X. Cabrini, Ascension, St. Eugene and St. Michael’s parishes, all in L.A. Among his associate pastor assignments were St. Raymond in Downey, St. Maria Goretti in Long Beach and St. Hillary in Pico Rivera.

On Sunday afternoon, Sacred Heart Church hosted a prayer service and vigil near O’Connell’s home. Sacred Heart parishioner Lourdes Kristen said her congregation naturally trusted him because he had such a humble approach.

“You could see God through his eyes,” she said.

Staff writer Ruby Gonzales contributed to this report.