CAP-HAITIEN, Haiti — A priest told mourners at a memorial service Thursday for slain President Jovenel Moïse that too much blood is being shed in Haiti as authorities warned of more violence ahead of his funeral.

The Rev. Jean-Gilles Sem spoke to dozens of people wearing white T-shirts emblazoned with Moïse’s picture.

“The killings and kidnappings should stop,” he said, noting that poor communities are the most affected. “We’re tired.”

The Mass at the cathedral in the northern coastal city of Cap-Haitien was about half-full as officials warned other events planned for later in the day could be canceled amid concerns over violence.

Moïse supporters kept interrupting the Mass as they cried out and accused Haiti’s elite of killing the president.

A man who identified himself as John Jovie stood outside the church with a group of men and threatened more violence if wealthy members of the elite from the capital of Port-au-Prince showed up for the ceremonies.

“We ask them not to come to the funeral,” he said. “If they come, we will cut their heads off. We will bring our guns out of hiding. …We want justice for Moïse.”

The mayor of Cap-Haitien arrived at the cathedral with heavy security as men with high-powered weapons stood watch during the entire Mass.

Demonstrations after the Mass turned violent on Thursday afternoon with protesters shooting into the air, throwing rocks and overturning heavy concrete barricades next to the seashore as businesses closed and people took cover.

A man yells for justice during a memorial service Thursday for assassinated Haitian President Jovenel Moïse in the Cathedral of Cap-Haitien, Haiti. Matias Delacroix/Associated Press

A heavily armed police convoy carrying unknown officials rushed through a barricade of flaming tires set up at the end of a bridge, with one vehicle turning over as the others continued on their way.

“This is real messed up since Jovenel died,” said David Daniel, who stood in the doorway of a restaurant he co-owns as he watched the scene unfold. But he said he doesn’t think it’s going to lead to anything productive. “Violence has been here in Haiti since I was a kid, so I don’t think violence is going to change anything.”

Some people signed a blue condolences book that the mayor’s office had set up near the cathedral as well-wishers stood before a portrait of Moïse and rows of candles whose flames flickered in the hot wind.

“My President. Go in peace. God sees everything. Fight for change,” wrote Louis Judlin, a 36-year-old electrician and father of two.

He said he is unemployed and struggles to find food to feed his children. “Life is truly hard for every Haitian. To eat, to go to school, to have health, transportation,” Judlin said.

The Mass was held a day after violence erupted in Quartier-Morin, located between Cap-Haitien and Moïse’s hometown. Associated Press journalists saw the body of a man whom witnesses said was killed during the protests organized by armed men who blocked roads with large rocks and burning tires.

“That’s the only way we have to demand justice,” Aurélien Stanley, a Moïse supporter, said of the violence. “If we don’t get justice for Jovenel, we will do whatever it takes to stop the funeral from happening.”

Armed police take cover near a barricade set on fire Thursday by protesters demanding justice for the assassinated President Jovenel Moise stands, in Cap-Haitien, Haiti. Matias Delacroix/Associated Press

Overnight, local media reported the burning of a nearby bridge that connected two communities.

Before the Mass began, several people stood at the entrance and shouted, “Justice for Moïse! Justice for Moïse!”

Inside, dozens of people wore T-shirts that read: “The fight for the ones that are weaker is continuing. Safe journey, President Jovenel Moïse.”

A private funeral for Moïse was planned for Friday as authorities continue to investigate the July 7 attack at the president’s home, in which he was shot several times and his wife seriously wounded.

Meanwhile, the U.S. State Department announced the appointment of Daniel Foote, a career member of the Foreign Service, as its special envoy for Haiti.

Foote will “engage with Haitian and international partners to facilitate long-term peace and stability and support efforts to hold free and fair presidential and legislative elections,” State Department spokesperson Ned Price said.

Haiti’s police chief, Léon Charles, said 26 suspects have been arrested so far, including three police officers and 18 former Colombian soldiers. Another seven high-ranking police officials have been detained but not formally arrested as authorities probe why no one in the president’s security detail was injured that night.