The first of 10 funerals for the 10 Black people killed in a Buffalo supermarket was held on Friday following an impassioned gathering of Black civil rights and community leaders at a church the night before where speakers pleaded with the nation to confront and stop racist violence.

Set against accused shooter Peyton Gendron’s silence in court earlier on Thursday, the community and relatives of Andre Mackneil, Geraldine Talley and Ruth Whitfield gave voice to the grief and anger coursing through East Buffalo.

Jaques “Jake” Patterson, 12, who lost his father, covered his face with his hands as his mother spoke, then collapsed into the arms of the Rev Al Sharpton, the veteran civil rights activist, and cried silently using his T-shirt to wipe his tears.

“His heart is broken,” said his mother, Tirzah Patterson, adding that her son was having trouble sleeping and eating. “As a mother, what am I supposed to do to help him get through this?”

Her ex-husband, Heyward Patterson, a 67-year-old church deacon whose funeral was held on Friday, was gunned down at Tops Friendly Market. So was Robin Harris’s 86-year-old mother and best friend, Ruth Whitfield, on a day when the pair were supposed to go see the touring Broadway show Ain’t Too Proud.

“That racist young man took my mother away,” Harris said, trembling and stomping her feet. “How dare you!” she shouted. “I need this violence to stop. We need to fix this, and we need to fix it now.”

Whitfield’s son, Darnell Whitfield Jr, who is the city’s former fire chief, told the Guardian his family “is grieving deeply, but we’re good”.

Whitfield spoke of the community’s response to the massacre. “I’m absolutely encouraged. This is our community and they’ve blessed us. This is what we do. We’ve come together as a community and a body of faith.”

The family had not yet broken the news to their father that his wife has passed. “We put our arms around him, but we’re still deciding how to do that.”

Mark Talley, holding a photo of his slain mother, Geraldine Talley, 62, said “I constantly think about what could have been done”.

Talley said the last time he heard from his mother was on Mother’s Day when she texted him to thank him for a gift. “I never would have thought it would be the last time I would speak to her or hear from her,” Talley said. “I never would have thought my mother would be shot dead – have a bullet go through her right temple on her head.”

Inaction on the threat of white supremacist violence, Talley added, led to last weekend’s bloodshed. “It’s like Groundhog’s Day. We’ve seen this over and over again,” he said.

Also at the families meeting was Ben Crump, the civil rights attorney representing several families affected by the tragedy. “I’m optimistic that these families are going to define the legacy of their loss and it won’t be this act of hate that defines them.”

Crump said he and attorneys working with him were determined to hold gun manufacturers and distributors responsible. “We’re going to use the right weapons to fight hate. That is, we’re going to use intellect, diplomacy and strategic thinking. That’s what we need to fight hate, because this white supremacy is the most dangerous thing in the world.”

Others said that the swift response of Buffalo leaders – including the mayor, Byron Brown, the judiciary and a community group called the Peacekeepers – to get Gendron indicted quickly on Saturday afternoon after the shooting had helped to avert a destructive response to the shooting.

In an address at Antioch Baptist church in East Buffalo, Sharpton, whose civil rights activist group the National Action Network plans to cover funeral expenses for those killed, said America was faced with “a rightwing element” that was trying to take back civil rights advances.

“It’s time for us to start fighting back. Enough is enough. For all the viciousness and hate that was shown at Tops, the Black community didn’t break one window, burn down one store or turn over one car,” Sharpton said. “We’ve shown this nation what this nation’s never showed us – respect. We’ve shown that this time we’ll stand up and do it right.”

The Rev Gregory Witherspoon at Buffalo’s Faith Missionary Baptist church said: “We can’t complicate the issue. If people go out and start breaking windows then that’s the problem, not the real problem.”

Others said that a de facto truce between neighborhood gangs had held, despite widespread anger that Gendron had been allowed to surrender when, many felt, a Black man would probably have been shot.

“The police are chilling out. They’re not pulling anybody over because people are mad they didn’t kill that dude,” said Orlando Tate, a security guard. “They would have killed anybody else.”

At the funeral on Friday, several hundred mourners turned to honour Patterson, who was gunned down helping an elderly Tops customer load groceries into the car. The public open-casket viewing attracted as many as 1,000 members of East Buffalo’s Black community.

The mayor as well as police officials and Sharpton – who was asked by Patterson’s family to deliver the eulogy – were among the mourners at Lincoln memorial church.

“It’s very sad, tragic, and for what purpose?” said Karla Warburton outside the church. “He was fun-loving. He had a heart and he could sing.”

Tony Marshall, the lead driver at Tops, said: “It is going to be a tough day and we’ve got many more coming.”

Viola Brown and Denise Brown, her niece, said they were anticipating a tough week of services. “He was a real good person, always helping people with their groceries and giving them rides.”

Donna Robinson, a community activist who said all her family were residents of the East Buffalo zip code 14208, said she “would never sit by and be complicit. It’s not in my nature.

“I’m feeling very emotional because this was a friend of a family member and I know he did good things, great things, for the community,” Robinson added.

When Trump took office, she said, the Ku Klux Klan, “[which] had always been in the community, got empowered and took their hoods off”. Now, Robinson said, some people openly fly the Confederate flag in south Buffalo.

“The ones that used to have the hoods on are taking them off so you can see. Anyone with nominal intelligence can see that 18-year-old had help.”